Statistics Mastery for Grade 12

What is the mean of the following data set: 5, 10, 15, 20, 25?

• 15

• 10

• 20

• 25

Calculate the median of the data set: 3, 7, 9, 12, 15, 18.

• 9

• 12

• 10.5

• 15

Find the mode of the following numbers: 4, 4, 5, 6, 7, 7, 7, 8.

• 5

• 4

• 7

• 6

A researcher claims that a new teaching method improves test scores. If the p-value is 0.03, is the result statistically significant at the 0.05 level?

• The p-value indicates a failure to reject the null hypothesis.

• Yes, but only at the 0.10 level.

• Yes, the result is statistically significant at the 0.05 level.

• No, the result is not statistically significant at the 0.01 level.

In a class of 30 students, the average score on a test is 75. If one student scored 90, what is the new mean score?

• 75.48

• 80.00

• 74.50

• 76.00

Determine the range of the following data set: 12, 15, 22, 29, 30.

• 30

• 15

• 22

• 18

If the standard deviation of a data set is 4, what is the variance?

• 8

• 20

• 16

• 12

A study shows that 60% of participants prefer product A over product B. If the sample size is 100, what is the standard error of the proportion?

• 0.06000

• 0.04899

• 0.03500

• 0.07500

What is the 75th percentile of the following data set: 10, 20, 30, 40, 50, 60?

• 50

• 60

• 52.5

• 45

If a hypothesis test results in a p-value of 0.08, what can be concluded about the null hypothesis at the 0.05 significance level?

• We fail to reject the null hypothesis.

• We reject the null hypothesis.

• The null hypothesis is proven true.

• We accept the null hypothesis.