Advanced Math practice question

Answer: 197

99² − 98² = (99 − 98)(99 + 98) = 1 × 197 = 197.

Common wrong answers

If you answered 1

1 is 99 − 98, forgetting the factor 99 + 98.

If you answered 199

199 is 100² − 99², a slip in the numbers.

If you answered 9801

9,801 is 99² alone.

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