The sum of the reciprocals of two alternate natural numbers is \frac{7}{24}. What is the sum of the numbers?

  1. A. 12
  2. B. 13
  3. C. 14
  4. D. 16

Correct Answer: C. 14

Explanation

Let the numbers be x and x+2. Then \frac{1}{x} + \frac{1}{x+2} = \frac{7}{24}, which yields \frac{2x+2}{x(x+2)} = \frac{7}{24}. Cross-multiplying gives 7x^2 - 34x - 48 = 0, solving which yields x=6. The numbers are 6 and 8, and their sum is 14.

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