What s measures. Add 2 to each of the numbers in data set

(a) in the previous exercise. The data are now 6 2 3 6 5 8.

(a) Use a calculator to find the mean and standard deviation and compare your answers with those for data set

(a) in the previous exercise. How does adding 2 to each number change the mean? How does it change the standard deviation?

(b) Without doing the calculation, what would happen to x and s if we added 10 to each value in data set

(a) of the previous exercise? (This exercise demonstrates that the standard deviation measures only spread about the mean and ignores changes in where the data are centered.)

262 CHAPTER 12 Describing Distributions with Numbers