What is the sum of two consecutive even numbers if the difference of their squares is 84?

Aptitude Problems on Numbers Difficulty: Easy
Choose an option
  • A
    40
  • B
    42
  • C
    44
  • D
    46

Answer

Correct Answer: 42

Explanation

Problem restatementLet the even integers be x and x + 2. Given (x + 2)2 − x2 = 84, find x + (x + 2).

Concept/ApproachUse the identity (a + b)(a − b) = a2 − b2, or expand directly.

Step-by-step calculation (x + 2)2 − x2 = 4x + 4 = 84 4(x + 1) = 84 → x + 1 = 21 → x = 20 Sum = x + (x + 2) = 20 + 22 = 42

Verification/AlternativeSquares: 222 − 202 = 484 − 400 = 84, consistent.

Final Answer42

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