Phone Orders the L.L.Bean Catalog Department That Receives the Majority of Majority

Short Answer

Phone Orders
The L.L.Bean catalog department that receives the majority of its orders by telephone conducted a study to determine how long customers were willing to wait on hold before ordering a product.The length of time was found to be a random variable best approximated by an exponential distribution with a mean equal to 3 minutes.
-{Phone Orders Narrative} What proportion of customers having to hold more than 1.5 minutes will hang up before placing an order?