Mary is 10 years old 14 years ago means she is 10 + 14 = 24 years old now.

Mary's age = 24 years

Let's assume that x years ago Marry was as old as Ann is now, that is:

Ann's age now = 24 - x

Also:   Mary = 2(24 - x - x)

24 = 2(24 - x - x)

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click here to see the equation solved for x

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x = 6 years

Ann = 24 - 6

Ann = 18 years

Ann is 18 years old now.