Math 110 Name:

Quiz 10

Assume that at a particular company, the amount of time that customers are left on hold is normally distributed with a mean of 180 seconds and a standard deviation of 20 seconds.

1. What percentage of their customers wait on hold for less than 180 seconds?
   

 

2. What percentage of customers wait on hold for more than 220 seconds?
   
   
   
   
    

    

3. For what percentage of the customers is the wait time between 170 and 190 seconds?