Math 9 LG 14 Practice Quiz #1

Name:

Multiple Choice
Identify the choice that best completes the statement or answers the question.

In which situation is there no influencing factor?

a.	After a baseball game, the people leaving the stadium are surveyed to determine their favourite sport.	c.	Every household in the city is mailed a survey asking, “Do you think tulips should be planted in the city parks?”
b.	A teacher asks her class to complete an anonymous survey with the question, “What is your favourite subject?”	d.	A teacher asks her class to complete a survey and print their names on the top of the survey.

Which of the following questions is free from influencing factors?

a.	Do you prefer chocolate or vanilla ice cream?	c.	If you use a computer at home, how much time per week do you spend using it?
b.	Which of these four colours is your favourite: red, blue, green, or yellow?	d.	How much money do you make at your part-time job?

A stratified sample is created by

a.	choosing respondents from the population who are easy to access	c.	dividing the population into groups and then choosing the same percent of respondents from each group
b.	inviting the whole population to participate	d.	choosing respondents from the population at random

Which population would you use if you were asking: “Are Canadian voters supportive of the Prime Minister?”

a.	a sample from the voting-age population of Canada	c.	the entire population of Canada
b.	all adults between 21 and 65 years	d.	all the people who voted in the last federal election

What makes this graph misleading?

a.	The representation of Indira’s calls is shorter than the others.	c.	The representation of Samantha’s calls is taller than the others.
b.	The representation of users’ calls is not a consistent width.	d.	The representation of each user’s calls is a different height.

A random sample is created by

a.	inviting the whole population to participate	c.	dividing the population into groups and then choosing the same percent of respondents from each group
b.	choosing respondents from the population who are easy to access	d.	choosing respondents from the population at random

Students are surveyed to find out their favourite sport. What method of selection will produce an unbiased sample?

a.	ask only the people who play sports	c.	ask every 5th person on the school list
b.	ask only the boys	d.	ask the first 20 people who leave the basketball game

Use the information provided to answer the following question(s).

Ms. Jenkins gave her class a quiz worth 15 points. After marking the first 4 quizzes, she predicted that the class would not do well on the test. The quiz scores are shown below.

6	6	9	8	12
12	13	15	9	11
11	12	8	15	9
10	14	12	15	11
7	9	4	6	9
12	12	14	10	11

What statement best describes this situation?

a.	Ms. Jenkins’ conclusion is valid because the sample is representative of the class.	c.	Ms. Jenkins is making a false prediction because the sample mean is not the same as the mode.
b.	Ms. Jenkins is making a false prediction because the sample does not represent the population.	d.	Ms. Jenkins’ conclusion is valid because the sample is taken from the class scores.

This line graph shows the number of baskets scored by Julie and Erica during six games. A clearer way to show this comparison might be to use a

a.	double bar graph that records the number of baskets each player scored in each game	c.	bar graph to show the total number of baskets scored in each game
b.	pictograph showing the total number of baskets scored in each game	d.	circle graph showing the percent of baskets each player scored during the season

10.

Which of the two graphs would you use if you wanted to know the total number of plants in the garden?

a.	The circle graph, because it is easy to add the percents.	c.	The circle graph, because it tells you there are 100 plants.
b.	The pictograph, because you can see how many carrot plants are in each picture.	d.	The pictograph, because the symbols are easy to count.

Short Answer

11.

As a group of music fans leave a concert, they are asked to identify their favourite band.
a) What influencing factor will affect the survey responses? Explain.
b) How could the bias be removed?.

12.

Identify the sampling technique used in each survey. Explain your selection.
a) A television host asks for opinions by selecting and interviewing people in front of the downtown studio.
b) A computer is programmed to randomly select 100 names from a club’s membership list.

13.

For the following situation, identify whether there is bias. If so, identify the bias. Then, rewrite the statement to correct it.

Ask horseback riders if they would support building a public park on the site of their stable.

14.

A group of BC Lions fans are asked who they think will win the next Grey Cup.
a) Is this an appropriate sample? Explain.
b) What could be done to improve the sample?

15.

A farmer wants to check his corn crop for signs of ear rot. Identify each of the following sampling methods the farmer could use.
a) Assign a number to each stalk. Randomly select a starting stalk number and then inspect every tenth stalk after it.
b) Sample 10% of the stalks closest to the road.
c) Divide the crop into sections and randomly select 10% of the stalks in each section.

Problem

16.

a) From the pictograph, which fruit seems to sell the best? Explain.

b) Does it seem that more cherries were sold or more peaches? Explain.
c) How should the pictograph be redrawn to represent the data more accurately?

17.

For each situation, identify and describe any factors that may influence the collection of data.
a) A sales representative e-mails a survey to you. In exchange for your participation, you will have a chance to win a trip for two people to a destination you choose. There is no other information.
b) An interest group surveys community residents about whether or not they would support a curfew for teens. The survey is being conducted the week after several incidents of vandalism at the high school were reported in the newspaper.
c) A village council wants to know if residents are in favour of building a new skating arena. The council decides to survey 500 people at the next hockey game.