1) A recent study showed the average cell phone life is 24.3 months with a standard deviation of 12 weeks. ( Need the distributions shown. )

a) If one cell phone is randomly selected, then what is the probability the cell phone will last more than 23.8 months? (Assume the data is normally distributed)

Answer- State the Z value is_____

The probability that_____

b) If the cell phone company only wants to warranty 2.5% of the phones, for how many months should they warrant the cell phones?

Answer- State the Z value is_____

The probability that_____

c) If a large company purchases 100 cell phones for their employees what is the probability that mean life of the phone is less than 25.1 months OR more than 24.3 months.

The probability that____