Question: Perform the requested Operation:

a. Two brands of batteries have a mean of 40hrs. If the standard deviation of Battery type A

is 2 hours and that of type B is 3 hours, which brand is more dependable?

b. Stock A has a normal (average) price of $10 with a standard deviation of $2.5 and is currently selling at $14. Stock B sells normally for $5, has a standard deviation of $1 and is currently selling for $9. As an investor, you own both kinds of stock and want to dispose of one. In the absence of any other information, which one should you sell?