Records maintained by the office of budget in a particular s

Records maintained by the office of budget in a particular state indicate that the amount of time elapsed between the submission of travel vouchers and the final reimbursement of funds has approximately a normal mean of 36 days and a population standard deviation of 3 days.

a. What is the probabilty that the elapsed time between submission and reimbursement will exceed 30 days?

b. If you had a travel voucher submitted for more than 55 days ago, what might you conclude?

Solution

a)

P( x > 30)

P( z > [30-36] / 3)

P( z > -2) = 1 -0.0228 = 0.9772

b)

P( z > [55-36] / 3 )

P( z > 6.33) = 0.000005

I migh conclude that is a value very unusual because the probability is almost 0