Algebra practice question

Answer: 15

Let the son be s: s + 30 = 3s, so 2s = 30 and s = 15.

Common wrong answers

If you answered 10

10 comes from s + 30 = 3s solved as 3s = 30.

If you answered 30

30 is the age difference, not the son's age.

If you answered 45

45 is the father's age.

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