Advanced Math practice question

Answer: 15

4² − 1 = 16 − 1 = 15.

Common wrong answers

If you answered 7

7 is 2(4) − 1, doubling instead of squaring.

If you answered 9

9 is (4 − 1)², subtracting before squaring.

If you answered 17

17 adds 1 instead of subtracting.

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