CLEVER BLONDE

A blonde, a brunette and a red head were stranded at sea on a boat. It was 100 miles to the nearest land. The red head decides that she is going to try to swim the 100 miles. She makes it 25 miles before she gets too tired and drowns. The brunette tries to swim the 100 miles. She makes it 35 miles before she gets too tired and drowns. The blonde realizing that the other two have drowned tries to swim the 100 miles. She swims 50 miles, decides that it's too far, and swims back.