Statistics

Question 1 of 20

Determine which of the four levels of measurement is most appropriate for the statement below.

Ages of survey respondents.

A. Ratio                 B. Interval          C. Ordinal            D. Nominal

Question 2 of 20

5.0 Points

A student wanted to know the favorite lunch at a large high school with a closed campus. What is the first step in conducting a statistical study to answer the question?

A. Select a random sample of students.

B. State the goal of the study precisely.

C. Select a random sample of students and teachers.

D. Select a random sample of teachers.

Question 3 of 20

5.0 Points

A botany student counted 11 blades of grass in one square centimeter of lawn and measured the lawn as a rectangle 61 m by 31 m. She reported that there were 208,010,000 blades of grass in the lawn. The precision of her conclusion:

A. correctly represents her measurements.

B. is less than her measurements warrant.

C. could be greater if she used a more precise calculator.

D. is excessive given her measurements.

Question 4 of 20

5.0 Points

Convert 5/16 to a percent.

A. 31.25%            B. 0.3125%        C. 3.125%              D. 0.03125%

Question 5 of 20

5.0 Points

Data has been collected from a representative sample of a well-defined population to answer the question: “How much money does the average senior male at Normal Community High School have in his pockets at the end of the school day on Friday?” The next step in the study is to:

A. determine the margin of error.

B. summarize the data with a sample statistic.

C. use the collected data to make inferences about the population.

D. summarize the data with a sample parameter.

Question 6 of 20

5.0 Points

A homeowner put a brand-name fertilizer/weed killer on half of his lawn and a generic fertilizer/weed killer on the other half. After three weeks, the generic side had 1 weed per square meter, the other side 1.7 weeds per square meter. The generic side required two mowings in the 3 weeks, the brand-name side one. The homeowner concluded that the generic was superior to the brand-name. Determine which evaluation guideline applies best in questioning the results of the described study.

A. Consider possible confounding variables.

B. Consider the sample.

C. Consider the type of study.

D. Consider the source.

Question 7 of 20

5.0 Points

A poll of 700 persons attending the Taste of Chicago showed that 455 persons, 65% of the sample, believed that the food was overpriced. It is estimated that 1,250,000 persons attend the Taste. Statistics suggest that, although 65% plus or minus 5% of attendees believe that the food is overpriced, the Taste is a popular event. The raw data of the study is (are)

A. 65% of the sample.   B. 700 persons, 455 persons.

C. 1,250,000 persons, 700 persons, 455 persons.

D. (60%, 70%).

Question 8 of 20

5.0 Points

The results of a poll are stated as follows: “Based on a survey of 156 randomly selected students, 90% of the student body of 2870 students agree that no student should have to take final exams in two consecutive exam periods”. If 2578 students actually agree, then what is the absolute error in the reported result?

A. 5 students

B. 287 students

C. 0.17%

D. 292 students

Question 9 of 20

5.0 Points

Two statements are given below. Select the statement for which a ratio of the measurements is meaningful. State “Neither” or “Both” if appropriate.

 

1 – Kasheta ran the race in 22.3 sec, and Louisa ran the same race in 26.4 sec.

 

2 – Juan gets out of school at 2:45 PM, and Aito gets out of school at 3:15 PM.

 

A. Kasheta ran the race in 22.3 sec, and Louisa ran the same race in 26.4 sec.

B. Neither

C. Both

D. Juan gets out of school at 2:45 PM, and Aito gets out of school at 3:15 PM.

Question 10 of 20

5.0 Points

Compared with a metric scale that has grams as the smallest division, a scale with milligrams as the smallest division:

A. will guarantee measurements that are more accurate, but not necessarily more precise.

B. will guarantee measurements that are more precise and more accurate.

C. will guarantee measurements that are more precise, but not necessarily more accurate.

D. will not guarantee measurements that are more accurate or more precise.

Question 11 of 20

5.0 Points

Convert 5.65 to a percent.

A. 565%               B. 5.65%                C. 0.565%           D. 56.5%

 

Question 12 of 20

5.0 Points

Which is the best fertilizer for Mr. Jimenez’ backyard grass? Select the type of study most appropriate to the question.

A. Experimental               B. Experimental blinded                 C. Case-controlled observational

D. Observational

Question 13 of 20

5.0 Points

In a survey of 80 high school football players who committed to play in the Division III CCIW conference, 64 said that they would work out in their high school weight rooms in the summer before college. The margin of error for the survey was 6%. A census of all CCIW football players (not just freshmen) showed that 59% worked out at their high schools. One can conclude that:

A. the subjects were less than forthcoming in their responses to the survey.

B. the sample was not representative of the population.

C. there must have been an error in the determination of the margin of error.

D. the census results are consistent with the confidence interval of the study.

Question 14 of 20

5.0 Points

The size of an e-mail file is stated as 210 kB, but the file size is actually 220.5 kB. What is the absolute error?  A. 5%             B. 10%        C. 10.5 kB               D. -10.5 kB

Question 15 of 20

5.0 Points

The father of a junior high school student wants to determine the most popular book among junior high students. Select the sample with the least potential bias.

A. A randomly selected group of 10 book sellers

B. A randomly selected group of 30 junior high students

C. A randomly selected group of 30 junior high students leaving the public library

D.The group of 30 junior high students attending the birthday party of the

researcher’s child

 

Question 16 of 20

5.0 Points

One month before a recall election, a poll of 500 Wisconsin voters showed that 46% planned to vote for the Democratic challenger Tom Barrett and 45% planned to vote for Republican Governor Scott Walker. Undecided voters constituted another 9%. The margin of error was 5 percentage points. What conclusion can you draw from this poll?

A. Barrett will win the election.

B. Walker can’t get over 50% of the votes.

C. The race is too close to call.

D. No one will win.

Question 17 of 20

5.0 Points

Compared with a stopwatch that gives readings as –. – seconds, a stopwatch that gives readings as –. – – seconds is:  A. more accurate, but not necessarily more precise.

B. more precise and more accurate.

C. not necessarily more precise or more accurate.

D. more precise, but not necessarily more accurate.

Question 18 of 20

5.0 Points

A U.S. government report stated that, “With bank interest rates around 1.0%, 8% of wage earners believe it worthwhile to keep money in a savings account. However, at 3.0% interest, 36% of wage earners believe it worthwhile to keep money in a savings account. The margin of error for both studies is 4 percentage points.”. A proper conclusion from the studies is that:

A. increasing the interest rate from 1% to 3% will increase the number of persons saving money in a savings account.

B. increasing the interest rate may well have no effect on the number of persons saving money in a savings account.

C. increasing the interest rate will increase the number of persons saving money in a savings account.

D. the interest rate difference between 1% and 3% may well have no effect on the number of persons saving money in a savings account.

Question 19 of 20

To avoid working late, a quality control analyst simply inspects the first 100 items produced in a day. Identify the type of sampling used.

A. Stratified        B. Cluster             C. Convenience                D. Random

 

Question 20 of 20

Suppose that the cost of a statistics text was $50 in 1985 and is $100 in 2000. What is the ‘Statistics Text Index’ number, rounded to the nearest tenth, for the 2000 edition with the 1985 price as the reference value?

A. 20.0                B. 200.0                  C. 50.0                 D. 2.0