Edmund wants to buy a secondhand PlayStation 3

(PS3) and he surveys the selling price from three different sources. He can purchase a PS3 from a friend, from a retail shop, or online. The following are the average and standard deviation values he finds through the three different sources:

Friends Retail Shops Online Average Price ($) 65 80 75 Standard Deviation ($) 6 9 15

a. Determine what decisions Edmund can make from the average prices and the standard deviation values for his purchase.

b. If Edmund needs to make a decision based on the consistency of the selling price, which is the best source for him to go?

c. If the selling price is symmetrically distributed, determine the chances that Edmund will purchase the PS3 for not more than $71 from the three sources.

d. If Edmund has $71, which source would be his best option?

e. Based on the results from parts a to

d, help Edmund select the best option.