- Elections A radio station asks its listeners to call and tell who their favorite
candidate is in an upcoming election. Sixty-eight percent of the callers prefer a
certain candidate, so the radio station announces that the candidate will win the
election. Is the conclusion valid? Explain.
Ch al l en g e 39. Dat a Co l l ect i o n You want to find out what kinds of pets the families of students
attending your school have.
a. Write an unbiased question for your survey. Will you be collecting quantitative
or qualitative data?
b. Choose a population and sampling method. Describe them both.
c. Collect the data as you described and display the results in a graph.- Writing A toothpaste company reports that four out of five dentists recommend
their toothpaste. What information do you need to know about the survey to
determine whether the results are unbiased?
St a n d a r d i ze d Test Pr ep
^SAT/ACT 41. What is the solution of the equation ^ — 11 = 19?
CD 8 CD 16 CD 30 CD 60- What is 0.0000212 written in scientific notation?
CD 2.12 X 105 CD 2.12 X 10~5 CD 21.2 X 10-6 CD 2.12 X 1(T6 - 40% of what number is 50?
CD 155 CD 125 CD 20 CD 2
Sh o r t 44. A reporter is trying to predict who will win an open seat on the city council.
^Response Her plan is to ask 20 coworkers who they think will win. Will this plan give a good
sample? Explain.
Mixed Review
- Of 30 test scores, 12 are less than or equal to 85. What is the percentile rank Se e Le sso n 12- 4.
of a test score of 85? - There are 15 bands in a competition. The judges give 9 bands a score of 7.5 or lower.
What is the percentile rank of 7.5?
Solve each inequality. 4/b See Lesson 3-4.- 4 — 3a < 3n — 2 48. 3(x - 2) < 6x + 3 49. 2.7 + 2b > 3.4 - 1.5b
G e t R e a d y! To p r e p a r e f o r Lesso n 1 2 - 6 , d o Ex e r ci se s 5 0 - 5 2.
Write each fraction in simplest form. ^ ^ ee P1
,-n 5 • 4 • 3 • 2 • 1 ,-1 7-6-5-4-3-2-1 „ 6 • 5 • 4 • 3 • 2 • 1
5U- 3 • 2 • 1 3 1 ■ 5 • 4 • 3 • 2 • 1 5 • 4 • 3 • 2 • 1G
Po w erAlg eb ra.com J Lesson 12-5 Sam p les and Surveys j 759