A+ Answers



1. Research shows that 14.3% of persons 20-25 years old and 59.9 % of persons 60-65 years old vote. What is the absolute increase from the younger group to the older group to the nearest point?
A. 77%
B. 336%
C. 436%
D. 47%
2. Research shows that 14.3% of persons 20-25 years vote and 59.9% of persons 60-65 years old vote. What is the absolute increase from the younger group to the older group; to the nearest point
A. 76 points
B. 310 points
C. -46 points
D. 46 points
3. A sideways histogram that includes a listing of data is called a
A. time-series graph
B. pareto chart
C. dotplot
D. stemplot
4. in a bar graph the height of each bar:
A. is proportional to its frequency
B. refer to the way its values are spread over all possible values
C. is inversely proportional to its frequency
D. is drawn with non-uniform widths
5. A rocket club markets its own rockets. The rockets go to a mean height of 1100 feet with a standard deviation of 60 feet. If the club fires 36 rockets, what is the probability that the mean height of the rockets will be greater than 1080 feet?
A. 0.9882
B. 0.9776
C. 0.9774
D. 0.9772
6. The advertising for a cold remedy claimed that no other cold remedy acts faster. In an experiment to compare that remedy with another one, it did act faster on average, but the result was not significant. What does that mean?
A. The difference was so small that it could have happened by change even if the remedies were equivalent.
B. The difference was so small that it could have happened by change even if the remedies were not equivalent.
C. The probability of the observed difference occurring by chance if the two remedies are equivalent was less than 0.05
D. The population mean response times are different, but the samples didn’t show.
7. If a quarterback completes 67% of his passes, what is the probability that he will not complete his next pass?
A. 0.67
B. 0.33
C. 0.23
D. 0.03
8. There are 318 teachers at a college. Among a sample of 115 teachers from this college, 67 have doctorates. Based on this sample, estimate the population proportion of teachers at this college with doctorates.
A. 0.42
B. 185
C. 0.61
D. 0.58
           
9. The standard score for a two-tailed test is 2.0. What is the P-value?
A. 0.9772
B. 0.0456
C. 0.0228
D. 97.72
10. Which of the following statement is true?
A. The t distribution cannot be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population.
B. The t distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from symmetric population.
C. The p distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from symmetric population.
D. All of the above is true.