Beef Stroganoff, a well-known underworld figure, must drive ten miles to rendezvous with his associates, Clams Marinara and Froglegs Sauteé. It will be necessary for Beef to average 40 mph for the 10 miles in order to be on time. The first 5 miles are in town, and Beef averages 20 mph there. For the second 5 miles, in open country, how fast must Beef drive to be on time? Being late is not an acceptable option; Clams and Froglegs will divide the loot without him.
Solution
Beef loses. To average 40 mph for ten miles means he has only 15 minutes to make it to the rendezvous. Alas, in going the 5 miles through the city at 20 mph, he used all 15 minutes. He cannot make the rendezvous on time no matter how fast he goes