Algebra practice question

Answer: 20

m + d = 32 and m − 4 = 2(d − 4). The second gives m = 2d − 4; substituting, 3d − 4 = 32, so d = 12 and m = 20.

Common wrong answers

If you answered 12

12 is the daughter's age.

If you answered 16

16 is the mother's age four years ago.

If you answered 24

24 comes from m = 2d without the four-year shift.

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