Name__________________________________

Math 210

Spring 2002

Quiz # 10B

Dr. McCullough

1. ) The waiting time, x, at a certain bank is approximately normally distributed with a mean of 3.7 min and a standard deviation of 1.4 min.

a. ) Find the probability that a randomly selected customer has to wait less than 2.0 min.

b. ) Find the value of the 75^th percentile for x .

2. ) Find - .

3. ) If 30 % of all students entering a certain university drop out during or at the end of their first year, what is the probability that more than 600 of this year’s entering class of 1800 will drop out during or at the end of their first year ?