Three old friends met at a livestock market. 

“Look here,” said Ronnie to Rueben, “I’ll give you six of my pigs for one of your horses, and then you’ll have twice as many animals here as I’ve got.”

“If that’s your way of doing business,” said Roger to Ronnie, “I’ll give you fourteen of my sheep for a horse, and then you’ll have three times as many animals as I.”

“Well, I’ll go better than that,” said Rueben to Roger; “I’ll give you four cows for a horse, and then you’ll have six times as many animals as I’ve got here.”

Undoubtedly, this was a very primitive way of bartering animals, but it is an interesting little puzzle to discover just how many animals Rueben, Ronnie, and Roger must have taken to the livestock market.