Advanced Math practice question

Answer: 7

1/x + 1/y = (x + y)/(xy). So (x + y)/12 = 7/12, giving x + y = 7. (The numbers are 3 and 4.)

Common wrong answers

If you answered 12

12 is xy.

If you answered 84

84 is 7 × 12, multiplying instead of matching numerators.

If you answered 7/12

7/12 is the reciprocal sum, not x + y.

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