This is an interactive mathematical and logic puzzle prepared for anyone interested in school-level math and critical thinking.

## Challenge:

12 years ago Michael was X times as old as Ryan was. If Michael is now 27 years old, how old is Ryan now in terms of X?

**A-** \(\frac{x}{15}\)

**B-** \(15x\)

**C-** \(\frac{15}{x}-12\)

**D-** \(\frac{15}{x}+12\)

**E-** \(\frac{x}{15}+12\)

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The correct answer is D.

12 years ago Michael was 15 years old. At that time, he was X times as old as Ryan was. Plug is a value for X. Let’s say X is 3. Therefore, Ryan was 5 years old 12 years ago. Now, Ryan is 17.

Plug in 3 for X and check all 5 options:

A. \(\frac{15}{3} = 3\),

B. \(15 × 3 = 45\),

C. \(\frac{15}{3} – 12= -7\),

D. \(\frac{15}{3} + 12 = 17\)! Bingo

E. \(\frac{3}{15} + 12 = \frac{123}{15}\)