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  Number & Math Play

Found and Lost
 
Q Eleanor found $4. Putting that $4 together with the money she had before her good luck, she now had 5 times the amount of money she would have had if she had lost $4. How much money did Eleanor have before she found the $4?


 
A Before Eleanor found the $4, she had $6. If she had lost $4 from the $6, she would have had only $2 left. The $4 she found plus the $6 she already had means she now has $10, which if 5 times the $2 should would have had if she had lost $4 instead of finding $4.

STRATEGY: Guess and check.

Source: Inspired by a puzzle inPut on Your Thinking Cap,Helen Jill Fletcher. New York: Abelard-Schuman, 1968.