Choose the correct answer

The data set represents the responses of 15 students who were asked how many text messages they send in a day.

{55, 50, 54, 51, 52, 53, 50, 51, 2, 56, 55, 56, 54, 57, 55}

The best measure of center for this data set is the MEAN, MEDIAN, RANGE, or IQR and the value is 51,52, 53, or 54.

Which data set has a wider spread? Why?

Set A: {9, 11, 24, 11, 4, 20, 16, 7, 18, 15, 28, 6} Set B: {9, 12, 15, 3, 21, 24, 5, 9, 16, 21}

Set A or Set B has a wider spread because: its mean is greater or its range is greater

The number of music CDs sold weekly by a store follows a normal distribution with a mean of 455 and a standard deviation of 65. Which sentence summarizes this information?

A. There is an 84% chance that the shop sells more than 390 CDs in a week.

B. There is a 34% chance that the shop sells more than 390 CDs in a week.

C. There is a 34% chance that the shop sells fewer than 390 CDs in a week.

D. There is a 68% chance that the shop sells fewer than 390 CDs in a week.

E. There is a 95% chance that the shop sells more than 390 CDs in a week.

The income distribution in a county is a normal distribution with a mean income of $10,000. The top 2.5% of the wage earners earn $18,000 or more. Which sentence most closely summarizes this information?

A. 68% of the wage earners earn less than $14,000 each.

B. 16% of the wage earners earn less than $14,000 each.

C. 55% of the wage earners earn less than $14,000 each.

D. 84% of the wage earners earn less than $14,000 each.

E. 95% of the wage earners earn less than $14,000 each.