Chapter 3: Collecting, Organizing, and Displaying Data

Transcription

1 Chapter 3: Collecting, Organizing, and Displaying Data Getting Started, p. 9. a) To find the favourite colour in the class, take a census. Since the number of students in a class is not too large, a census is reasonable. b) Since many families live in Ontario, a census would be difficult to perform. Therefore, collecting data from a sample is a better choice. c) For example, since the size of a community can be very large, a collection of data from a sample is the better choice. d) This depends on the number of students in Grade. If it is a big number, collect the data from a sample; if there are not very many students in Grade, perform a census.. Circle A matches the data for the listening time for all ages. Circle B matches the data for the listening time for ages to. 3. a) Reading the values from the graph, i) ii) iii) b) To determine the year with the greatest growth, find the two consecutive years in which the difference is the greatest. In 99 99, the growth was the greatest. It increased by 3. c) The growth decreases when the population decreases. This happens in. The decrease was.. a) intervals are used b) The mark range is from to 93. Most students get a mark in s. A few students get marks below and a few students get marks above 9. One person failed the assignment.. Average Monthly Sunshine in September Kamloops, BC Schefferville, QU St. John s, NF Sydney, NS Prince Rupert, BC Coppermine, NWT Sunshine (h). The mean is found by adding all the numbers in the series and then dividing by. = total value of the data = ( ) = = 3 The median of the set of data is the number in the middle. The data in order from least to greatest is 9,,,,,, 33, 3. The median is the average of the fourth and fifth numbers. median = ( + ) =. The mode is the data point that occurs most often. The mode is. 3. Organizing and Presenting Data, pp For example, a) a line graph, because you are trying to predict something b) a circle graph, because you are working with percentages. c) a scatter graph, because you are looking for a relationship. d) a pictograph, because it is easy to find specific data quickly.. For example, a) a line graph or a scatter plot. A line graph is most appropriate because you are looking for a trend. b) a bar graph, a pictograph. A pictograph is most appropriate because it is easy to see who has made the most number of baskets.. c) a bar graph or a line graph. A line graph is most appropriate because you are trying to predict something. d) a bar graph, a pictograph, or a circle graph. A circle graph is most appropriate because you want to see the percentages of each type of garbage in order to distribute resources fairly. e) a bar graph, a pictograph, or a line graph. A line graph is most appropriate because you are looking for a trend. Nelson Mathematics Solutions 3-

2 . a) For example, USA Brazil China Japan Country Russian France Italy Canada Estimated Dog and Cat Populations for Various Countries in Number of dogs or cats dogs cats A comparative bar graph is chosen because the difference between dog and cat population and the difference from country to country can be seen easily. b) The longer the bar, the more cats or dogs there are in a country. Compare the lengths of the two bars to tell if there are more dogs or cats.. a) Gasoline used (L/ km) Speed Compared to Gasoline Used Speed (km/h) b) To find the driving speed for which the least amount of gas is used, locate the lowest point on the graph. The lowest point on the graph is km/h. So, the car uses the least amount of gas at about km/h. c) Gasoline used (L/ km) Speed Compared to Gasoline Used Speed (km/h) As shown in the graph, another speed at which 9. L of gas is used to travel km is approximately 3 km/h. d) For example, Gasoline (L/ d km) Speed Compared to Gasoline Used Speed (km/h) The amount of gas used to travel km at 9 km/h is predicted to be about. L.. a) Snack Type potato chips chocolate bar apple plain cereal bar candy carrot sticks Preferred Type of Snack 3 9 Number of students Before guest Afterk guest k As shown in the graph, the guest speaker convinced students to eat healthier snacks. b) A comparative bar graph is used because from its two different coloured bars, the lengths can be easily compared to find the answer.. For example, b) Preferred type of snack potato chips chocolate bar apple plain cereal bar candy carrot sticks 3 Number of students 3- Chapter 3: Collecting, Organizing, and Displaying Data

3 Snack type potato chips chocolate bar apple plain cereal bar candy Preferred Type of Snack. To find the number of hours spent watching television for both males and females who are over the age of eighteen, take the average. average = total = (. h +. h) =. h = 3. h Use a spreadsheet to make a bar graph like this. carrot sticks 3 9 Number of students c) More students in my class prefer unhealthy snack than the students in Gerald s Grade class. 9. There is no relationship between age and wealth. From the scatter plot graph, there is no obvious pattern in the data. The Ages of Billionaires Wealth (billions of dollars) 3 3 Age (years) 3.3 Using Electronic Databases, p. 3. Use a spreadsheet program to construct the graph. Time (hours). Time (hours) Average Number of Hours of Television Viewing per Week Ages - Ages - Average Number of Hours of Television Viewing per Week All ages Ages & over Ontario Canada Ontario Canada. a) The newspaper is read the most by Canadians. This might be because a lot of Canadians read newspapers on the way to work everyday in order to stay informed about current events. b) Female Canadians read more magazines and books than males. c) Comparative bar graphs can be constructed to represent the data in this database. For example, a comparative bar graph ca be constructed to compare the percentage of female and male Canadians who read books. The list of data needed is reorganized into the following table: Percentage of Canadians Male Female who read books At least a book a week At least a book a month At least a book every 3 months 9.. At least a book every months 9.. At least a book a year... a) For example, database for the rate of growth of the population of Canada is found at: Database for the rate of growth of the population of Toronto is found at: Percent Rates of Growth of the Population of Canada and Toronto 3 Year Canada Toronto Nelson Mathematics Solutions 3-3

4 . For example, database for the average total income in Canada is found at: Dollar ($) 3 Average Total Income in Canada Year For the last years, the average total income increased by about $. So at this rate, the average total income will be around $ in year (about years later). 9. a) and b) For example, Country Land Area (km ) GDP (billions of $US) Population (millions of people) Australia Canada China Japan Malaysia New.. Zealand Pakistan Russia Singapore..3.3 U. S 9 9, Country Literacy Rate (%) Life Expectancy (years) Australia. Canada 9 9. China. Japan 99.9 Malaysia.9. New Zealand 99.3 Pakistan.. Russia 99.. Singapore 93.. United States 9. c) For example, Japan, Singapore, Australia, Canada, New Zealand, United States, China, Malaysia, Russia, Pakistan. d) For example, I want to live in the countries with the highest life expectancy. Draw a graph comparing the life expectancy for each country. Time (years) Australia Canada China Japan Malaysia New Zealand Pakistan Russia Singapore United States Life Expectancy for Ten Countries Country. a) For example, create the new database with these fields: Country, Area (km ), Population, Imports to Canada (millions of $), Exports from Canada (millions of $), Continent. The first column can be China, Norway, Spain, Taiwan and USA. Then enter the remainder of the data accordingly. b) Copy and paste the database to a spreadsheet, sort the Continent column alphabetically first to find all the European countries together. Copy that section and paste it onto another spreadsheet. Sort the Population column in descending order to find the European country with the largest population. c) Copy and paste the database to a spreadsheet, sort the Continent column alphabetically first to find all the Asian countries together. Copy that section and paste it onto another spreadsheet. Make another column by using the Sum Formula to calculate the total and imports. Then sort the new column in descending order to find the Asian country that trades with Canada the most. d) Of the countries listed in the database, Spain comes closest to breaking even in trade with Canada since the difference between its imports to Canada and exports from Canada is the smallest. e) Canada exports the most to USA and the least to Norway. Mid-Chapter Review, p. 3. a) Percent 3 Percent of Two Provinces Adult Population with Various Levels of Schooling No higher than secondary Postsecondary nonuniversity University without a degree Schooling level Universtiy with a degree ON NB 3- Chapter 3: Collecting, Organizing, and Displaying Data

5 b) 3 Percent Percent of the Population with No Higher than Secondary Education NL PEI NS NB QC ON MB SK AB BC YT NT NU Province c) Nova Scotia is the most representative of Canada in terms of schooling because the percentages in each category of Nova Scotia are very close to the percentages for Canada. d) Ontario, British Columbia, and Yukon Territories are above the Canadian percentage for population with a university degree. e) New Brunswick and Newfoundland because they have the highest percent of No higher than secondary. f) For example, a comparative bar graph that compares each targeted province with Canada would be an effective type of graph to use. This graph would show the percentages of people with education no higher than secondary.. a) For example, a bar graph is used when the frequency in different categories of data needs to be shown, when populations of different provinces are compared, or when life expectancies of different countries are compared. b) A scatter plot is used to find a relation between average temperature and average rainfall per month over the period of a year, the m sprint times and age of the sprinters, and wealth of billionaires and their age. 3. The greater the size of the sample, the closer it is to the size of the population, which usually gives a more accurate result. Magda asks more students than Trevor, therefore her result is likely more accurate.. a) c) Use the Gross Income to find the percent of the total that North America grosses for each movie. Film Percentage of Total from North America (%) Titanic 3. Harry Potter 3. Star Wars. Jurassic Park 3. Lord of the Rings 3. d) Income ($US in thousands) Gross Income from North America and Overseas Titanic Harry Potter Star Wars Film Jurassic Park Lord of the Rings 3. Histograms, pp. North America Overseas 3. a) There are intervals in this histogram. Each interval s width is minutes. b) His data belongs to the minute interval. c) For example, I spend hour doing homework each day. So, my data belongs to interval.. Temperature range 3 3 Temperatures Compared to b) Use a Gross Income column and find the total income from North America and Overseas for each. Film Gross Income ($) Titanic 3 Harry Potter 9 Star Wars 93 Jurassic Park Lord of the Rings Temperatures (ºC) Nelson Mathematics Solutions 3-

6 . 3 Time Spend on the Computer Daily Time (min). a) Mean bowling score The data range is.9 9. =.. If multiples of five are used for the interval labels, there would be intervals, which is too many. So, multiples of are used. That makes six intervals from 9 to. Ravi s Mean Bowling Scores b) Scores c) a) The interval size is minutes in this histogram. There are intervals. b) His data belongs in the 3 minute interval. c) The total number of students is = 9. To get the percentage of the number of students who need 3 or more minutes to get to school, divide the frequency of that interval by the total number of students, and multiply by. 9 %.% So, approximately % of the total number of students need 3 or more minutes to get to school.. a) Juan could have used Manon s bar graph to create his histogram. Since the bar graph shows exactly how long each movie is, Juan can first record all the data from the bar graph, then organize the data into a frequency table, and then use the table to make the histogram. b) Manon could not have used Juan s histogram to create her bar graph because the histogram does not record the exact data. It only shows the number of times the data falls in a certain range. c) The benefit of making a histogram of the movie times is that the graph won t be too long, but it can still give a good idea of the running times of the movies. 9. The data range is.. = 3.. a) i) 3. 3 =., so make the interval size.. The three intervals will be. 3., 3..,... ii) For five intervals, the interval size can be.:..,. 3., 3..,.., and... b) intervals is more appropriate because using 3 intervals is not enough. c) Times Recorded for a m Race Time (s). Anna shows people have an age of, while Ben shows people have an age of 9. So, there are people has an age of. Since Ben shows 9 people are 9, there are people age 9 (since of those people are age ). But Anna shows there are people with an age of. Therefore, no one is years old. Ben also shows that people has an age of 9. Since nobody is, people are 9. Because Anna s histogram also shows that people are 3, people are 3 years old. Then from Ben s histogram where it shows 9 people are 3 39, people are 3 39 (since of those people are age 3). But Anna shows there are people who are 3, so no one is years old. So, Ben s people are 9 means people are 9. From Anna s work, people are. So, people are years old. At last, Ben shows that people are 9. Since there are people who are, no one is 9. A distribution of the ages that makes both histograms accurate is: 3- Chapter 3: Collecting, Organizing, and Displaying Data

7 Age (in years) Mean, Median and Mode, p.. a) The mean of the data is the average of the data. = total value of the data = ( ) = 3 =.3 Use a stem-and-leaf plot to find the median and the mode The median is ( + ) =. The mode is. b) Removing the greatest and least values: = total value of the data = ( ) = =. Use a stem-and-leaf plot to find the median and the mode The median is ( + ) =. The mode is. c) Since the median and the mode are the same after removing the greatest and least values, the mean changes the most.. a) The mean of the data is the average of the data. = total value of the data = ( ) =. 3. Use a stem-and-leaf plot to find the median and the mode The median is.. The modes are. and.9. b) The mean of the data is the average of the data. = total value of the data 9 = ( ) 9 = Use a stem-and-leaf plot to find the median The median is still. and the modes are still. and.9. Since the median and the mode are the same after removing the greatest and least values, the mean changes the most.. mean number of new subscribers per month = ( 393 ) = The mean number of new subscribers per month during that year was.. a) Of the given data, and 9 both occur twice while all the other numbers only occur once. since is the mode, the missing number must be. b) No, it is not possible to determine the missing value. The median of. that is given shows that the two middle numbers of the ten numbers are and 9. There are four numbers smaller than and three numbers greater than 9. So the missing number can be any number that is equal or greater than 9. c) Since the mean of the nine numbers is, the total value of the nine numbers is 9 =. The sum of the eight known numbers is = 3 So the missing number is 3 = 9.. Natalia made a total sale of $, which is greater than the mean of Eric s class. Adding a greater number will result in a greater mean. So if she moves to Eric s class, the mean of Eric s class will increase. Also Natalia s total sale is lower than her class. Removing a smaller number will increase the mean as well. So, if she moves to Eric s class, her old class s mean will also increase. Nelson Mathematics Solutions 3-

8 9. mean of the marks = ( ) =. =. List the marks from least to greatest:.,.,.,.,.,.,.,.,.,.,.. The middle mark is., so. is the median of the marks. a) The four marks whose removal would lower the mean score the most are the four greatest marks:.,.,.,.. mean = ( ) = 3. =. Since there are only marks left, the median is the fourth number of the marks, which is.. b) The four marks whose removal would raise the mean score the most are the four lowest marks:.,.,.,.. mean = ( ) =. =. Since there are only marks left, the median is the fourth number of the marks, which is... Make a stem-and-leaf plot to order the numbers Calculate the total value of the twelve numbers: total = = 3 a) To make the median, remove one number that is greater than, since there are five numbers smaller than, but six numbers greater than. For example, can be removed to make the median. b) Since the wanted mean is.9, the total value of the eleven numbers is.9 =.99, which is rounded to. Since the total value of the twelve numbers is 3, the number that needs to be removed is 3 =.. a) For example, the word lengths of the first words in a novel are:, 9,,,,,,,, 3,,,,, 3,, 3, 3, 3,,,,,,,,,, 3,,, 3,,,,, 3,, 9,,, 3,,, 3,,, 3,,,, 3,,, 3,, 3,,,, 3,,, 3,,, 3, 9, 3,, 3,, 3,,, 3,,,, 3,,, 3,,, 3,,,,,,, 3,,, 3,,, The word lengths of the first words in a textbook are:, 3,,,,,,,, 3,,,,,, 3,, 3,,,,, 3, 3, 3,,,,, 3,, 3,,,, 3, 3,,,,, 9, 3, 3,,,,, 3,, 9,,,,,,,,,,,,, 3,, 9,, 3, 3,,,,, 9, 3,, 3, 3,, 9,,,,, 3, 3, 9, 9,,,,,, 9,,, 3,,, b) The mean, median, and mode of the first words in the novel are., and 3 respectively. The mean, median, and mode of the first words in the textbook are.,., and 3 respectively. According the means and medians, the words in a textbook are much longer than the ones in a novel since the textbook s average word length is. and the novel s is.. In general, the lower the average word length, the higher the readability. c) For the novel: Remove the two longest words: and. Then, find the new mean, which is about.; find the new median, which is ; find the new mode, which is 3. For the textbook: Remove the two longest words: 3 and 3. Then, find the new mean, which is about.; find the new median, which is ; find the new mode, which is 3. So, only the modes and the median of the novel stays the same, the other three values decrease. 3. Communicating about Graphs, p. 3. For example: How did you create your graph?, How many meals did you eat or what is the total number of servings of food you had?, What other conclusions can you make from your graph?. a) For example, use a spreadsheet to draw a scatter plot of the values. Include a title and labels on the axes. Lifetime (hours) 3 3 Battery Life 3 3 Battery Number 3- Chapter 3: Collecting, Organizing, and Displaying Data

9 b) dots are above the h line, so there are batteries that had a lifetime longer than hours. Therefore the company s claim is false.. a) Add another column to the chart to determine the total number of gold, silver, and bronze medals for each country. Country Gold Silver Bronze Total Medals Germany/ 3 East Germany/ West Germany USSR/ 3 Unified Team/ Russia Norway United States 9 93 Austria Finland 9 Sweden Switzerland Canada For each region s total metals, add each of its country s total medals together. Region Country Region s Total Medals Scandinavia Sweden Norway = 3 Finland North Canada America United States = 9 Switzerland Austria Alps Germany/ = East Germany/ West Germany USSR USSR/ Unified Team/ Russia Therefore, the Alps region had the highest medal standings, followed by Scandinavia, North America, and the USSR/Unified Team/Russia. b) For example, draw a bar graph since you are comparing different values. Include a title and axis labels on the graph. Notice that the Alps has the highest bar, and the Unified team has the lowest bar. c 3 c Olympic Medal Standings by Region (9 ) 3 9 Alps Scandinavia North America USSR Region c) If the pattern from 9 to continues, the Alps will be the region that wins the most medals in the next Winter Olympics, followed by Scandinavia, North America and the Unified Team. Since the Unified Team represents one country in their region, they rank last in the region medal standings. The Unified Team will likely win the most medals as a country in the next Olympics if the pattern continues. Although the United States wins many medals as a country, North America does not rank high as a region since Canada doesn t win many medals.. a) For example, draw a line graph since you are showing a change. Include a title and labels on the axes. Notice that the population has always increased, but there has been the most increase between 9 and. 9 3 Population of Earth (billions) by Year 9 Year 9 b) For example, since there was about a 3. billion increase in the population between 9 and, you could assume that the Earth s population in will 3. billion greater than in the year. Therefore, estimate the population will be. billion + 3. billion = 9. billion. Nelson Mathematics Solutions 3-9

10 Chapter Self-Test, p.. a) Precipiataion in April (mm) Precipitation in January vs. Precipitation in April Precipitation in January (mm) The relationship between the precipitation in January and the precipitation in April is that a high amount of precipitation in January also generally means a high amount of precipitation in April. b) A scatter plot was an appropriate graph to use because the relationship between the precipitation in January and the precipitation in April was wanted.. a) The sample size that would make the mayor most confident that she made the correct decision is people. This is the largest sample size, so the mayor would get the opinion of the most people. This will probably give the most accurate results. b) The mayor might not use this sample size since it is too large. It would be hard to get that many people to answer the survey. It is an unrealistic sample size. 3. a) Precipitation Totals for Various Cities in Canada Charlottetown Dawson Calgary Edmonton Western Fredericton Cities Halifax Eastern Moncton Montreal Winter Fall For example, the western cities have less precipitation than the eastern cities of Canada. To compare the data from the eastern and western cities, create a comparative bar graph. Delete the unnecessary data from the chart, such as the precipitation during April and July, and the cities in central Canada. Have one set of bars represent the amount of winter precipitation, and the other set of bars represent the fall precipitation. To make it easier to analyze the graph, separate the western and eastern cities from each other. b) For example, it is not reasonable because the data only represents selected eastern and western cities in Canada. There are no cities from British Columbia that is represented in the data. Since British Columbia has a very diverse landscape with rainforests, mountains, and even deserts, the given data is not enough. Also, the data is only provided for two months of the year, which is not representative of their respective seasons.. a) Height (cm) 9 You need intervals to represent heights from cm to 9 cm. That s a range of cm. If multiples of two are used for the interval labels, you would have intervals, which is too many. If multiples of ten are used, you would have three intervals, which is too few. Choosing multiples of five gives six intervals. Start the first interval at because it s a multiple of five. b) 3 Heights of Shoppers Height (cm). a) Use a stem and leaf plot to organize the data Chapter 3: Collecting, Organizing, and Displaying Data

11 The median is 3 C and the mode is C. Calculate the mean adding all the temperatures, and dividing by 3. = total value of the data 3 = ( ) 3 = 3 = 3.93 The mean is about 3.9 C for April. b) Use another stem and leaf plot to organize the data after removing the three greatest and least values The median is 3 C and the mode is C. Calculate the mean by adding all the temperatures, and dividing by. = total value of the data = ( ) = 3 = 3. The mean is about 3. for April. Since the median and the mode do not change, the mean was the most affected. It dropped by. C. Chapter Review, p.. a) i) Look for the country with the highest life expectancy, then note that country s income. It is Japan, and the per capita income is $3 3 US. Now look for the country with the next highest life expectancy. It is Iceland, with an income of $ 9 US. In general, all of the countries with a life expectancy above, have per capita income above $9 US. If you look at the countries with the lower life expectancies, (between and 9), you will see that they have incomes lower than $3 US. Therefore, the general relationship between life expectancy and income is the higher the per capita income, the higher the life expectancy. b) People per Motor Vehicle People per Motor Vehicle vs. Per Capita Income 3 3 Per Capita Income (U.S. $) In countries with higher per capita incomes, there are fewer people per motor vehicle.. When conducting a survey, I would be more confident with the results from a census since you get the opinions of more people. With a sample, you are only getting answers from part of the population, and using that information to make a prediction for the entire population. But with a census, you have the actual data for the whole population. 3. You need intervals to represent distances from. km to km. That s a range of.9 km. If multiples of two are used for the interval labels, you would have 9 intervals. That s too many. If multiples of ten are used, you would have six intervals. Chose multiples of ten. Start the first interval at, and use seven intervals. Distance (km) Distances Employees Drive to Work Distance (km) Nelson Mathematics Solutions 3-

12 . a) b) The median is ( + ) =.. The mode is. c) Calculate the mean by adding all the values and dividing by. = total value of the data = ( ) = 39 =. The mean is.. d) The median is ( + ) =.. The mode is. Calculate the mean by adding all the values, and dividing by. = total value of the data = ( ) = 33 =. The mean is about.. Since the median and the mode do not change, the mean was the most affected. It dropped by.3.. The numbers in order are 3,, 9,,,,. The original median is and the original mean is about.. a) Adding to the series gives 3,, 9,,,,,. The median is ( + ) =.. It rose since there was a number added to the end of the series. The mean is 3.. This number rose since a very large number was added in comparison to the other numbers. b) Adding 99 to the series gives 3,, 9, 99,,,,. The median is (99 + ) = 99.. It dropped since there was a number added that was less than the previous median. The mean is.3. It rose slightly from the original since a number greater than the initial mean was added to the series. c) Adding to the series gives, 3,, 9,,,,. The median is (9 + ) = 9.. It dropped since the number added was less than the original median. The mean is 39.. It dropped significantly because a very small number was added in comparison to the other numbers.. a) Grade Lunchtime Beverage Preferences Juice % No beverage % Bottled Water % Milk % Grade Lunchtime Beverage Preferences No Beverage % Juice % Bottled Water % Milk % Organize the data in a spreadsheet and then use the graphing program on the computer to construct the circle graphs. Place titles on the graphs and label the sections of the circle graphs with percents. You can conclude from the graph that more Grade students prefer juice than Grade students. b) For example, to make the graph, combine the data so that it represents both grades. Type of Drink Number of Students bottled water + = 3 milk 9 + = 3 apple juice + 3 = orange juice 3 + = grapefruit juice + = no beverage + = 3 3- Chapter 3: Collecting, Organizing, and Displaying Data

13 Dear Principal, A recent survey conducted at our school asked Grade and students what beverage they prefer at lunchtime. The results are displayed in the following graph. Beverage Preferences at Lunchtime Grapefruit Juice % Orange Juice 3% No Beverage % Bottled Water % Milk 9% Apple Juice % As you can see from the graph, the majority of Grade and students at this school prefer orange juice, followed by bottled water and milk. Based on this information, I propose to you that the school offer orange juice, bottled water, and milk at lunch. Sincerely, A Student Cumulative Review: Chapters 3, pp. 9. Use a prime factorization tree So the prime factorization is = 3. The correct answer is B.. To determine which value is closest to, try squaring the given numbers. = = 9 = = Since is the closest to, must be the closest to. A is the correct answer. 3. To determine the result, use the order of operations. ( ) = ( ) = ( ) =. = 9.3 To three decimal places, the result is 9.3, which is D.. The four sets all contain the same numbers. Express these numbers in the same format, so they are easier to compare.. =.. =..... =.... =. = From least to greatest, the order is:.,....,.,.3 3,..... This is the order in A, so it is correct. Another solution method is: Since. is less than., B is incorrect. Since is less than, C and D are incorrect. Since one of the choices is correct and B, C, and D are incorrect, then A must be correct.. There are = 9 parts in total. Since they earned $3.9 in total, one part of this is $3.9 9 = $.. Maria worked for parts of time, so she should receive $. = $., or D.. Determine the unit rates of each traveller. Jacob travelled km in h, so his unit rate of speed is km h =. km/h. Alissa travelled 9 km in h, so her unit rate of speed is 9 km h = 99. km/h. 99. km/h is faster than. km/h, so A is the correct choice.. Multiply $3 by 3% to determine how much Marcy paid. $3 3%= $3..3 = $. D is correct. Nelson Mathematics Solutions 3-3

14 . The mouse is selling for % of its regular price, so the discount is % % = % or.. The discount is. $9.9 = $.9. B is correct. 9. Since a histogram is limited to comparing values over time and a bar graph is not, statement B is false.. The greatest score is. and the least score is.. Remove these scores. The sum of the other scores is = The mean is = 9.. D is correct.. a) The sum of the hourly rates for the restaurants is $. + $. + $9.9 + $. + $. + $. + $. + $. + $.9 = $.. The mean is $. 9 = $.. Without the greatest and least hourly rates, the sum is $. + $9.9 + $. + $. + $. + $. + $.9 = $9.. The mean is $9. = $.. For example, the mean without the greatest and least numbers better represents the hourly rates of pay since the greatest pay of $. is much higher than rest of the rates, the mean is greatly affected by it. So, the mean without the greatest and least rates better represents the average hourly rates of pay. b). Hourly Rates of Pay ($) The lowest rate of pay is $. and the highest is $.9, which gives a range of $. for the set of data. If multiples of. are used for the interval labels, there would be intervals. That s too many. If multiples of is used, there would be intervals if starting from $. and ending a $3.. The number of intervals is appropriate, so use multiples of. c) 9 3 Hourly Rate of Pay Rates of pay ($/h) The histogram shows that most common hourly rate of pay is about $. to $.99. But still a lot of rates are below $.. Only a few rates are above $.. d) You are looking for the least common multiple of 3 and, which is. Since there are 3 buttons in each package, then 3 = packages of buttons are needed. Similarly, since there are bookmarks in each package, then = 9 packages of bookmarks are needed. 3- Chapter 3: Collecting, Organizing, and Displaying Data