Multiple choice general knowledge math & puzzles

Man Wrinkle spent one-fourth of his life as a boy, one-eighth as a youth, and one-half as an active man. If Man Wrinkle spent 12 years as an old man, then how many years did he spend as an active man?

  1. 64

  2. 48

  3. 36

  4. 128
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let total life = x years. As boy: x/4, as youth: x/8, as active man: x/2, as old man: 12 years. Total: x/4 + x/8 + x/2 + 12 = x. Converting to eighths: 2x/8 + x/8 + 4x/8 + 12 = x, so 7x/8 + 12 = x, which means 12 = x/8, so x = 96 years. Active man period = x/2 = 48 years.

AI explanation

The fractions for boy, youth, and active-man stages add up to 1/4 + 1/8 + 1/2 = 7/8 of his total life, leaving 1/8 of his life for his years as an old man. Since that 1/8 equals 12 years, his total lifespan was 96 years, and his active-man years (half of 96) were 48.

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