There were three people stranded on an island: a brunette, a redhead and a 
blonde. The brunette looked over the water to mainland and estimated about 20 
miles to shore. So she announced, "I'm going to try to swim to shore." So she 
swam out 5 miles, and got really tired. She swam out 10 miles from the island, 
and she was so tired to go on, so she drowned. 
The second one, the redhead said to herself, "I wonder if she made it. I guess it's better to try to  get to the mainland than stayed here and starve." So she attempts to swim out. 
The redhead had a lot more endurance than the brunette, as she was so tired to go on, so she drowned. 
So the blonde thought to herself, "I wonder if they made it! I think I'd better try to make it, too. "So she swan out 5 miles,10 miles,15 miles, and finally 19 miles from the island. The shore was just in sight, but she said, "I'm too tired to go on! "So she swam back.