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  Number & Math Play

How Old?
Q Mary is twice as old as her brother and half as old as her father. In 22 years, her brother will be half as old as his father. How old is Mary now?

A Mary is now 22 years old.

From "an age-old puzzle" reappearing inThe World's Most Amazing Puzzlesby Charles Barry Townsend. New York: Sterling Publishing, 1993.