THE RACE TO MECCA

A rich Arab who loved puzzles died. In his will, he specified that his two sons race one another on horseback. They were to race to Mecca, which was 20 miles away.  The son whose horse finished last would inherit all his father's wealth.

The day of the race each brother rode his horse as slowly as he could. When night came, they had only gone one mile. At that rate they race would take at least three weeks, and what would happen when they reached the finish line?  That night they stopped at an inn. When they told the innkeeper about their problem, he thought for a minute. He then gave the brothers two words of advice, which they decided to follow.

Early the next morning, they rode off toward Mecca. But now they raced as fast as their horse would carry them.  What were the clever innkeeper's two words of advice?

Answer:

"Switch horses."