Multiple choice general knowledge math & puzzles

N positive real numbers have a product of unity. Their sum must be

  1. divisible by N

  2. equal to N + 1/N

  3. at least N

  4. a natural number

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

For N positive numbers with product 1, the AM-GM inequality states arithmetic mean >= geometric mean = 1, so sum >= N. Equality occurs when all numbers equal 1. Examples: if N=2 and numbers are 2 and 0.5, product=1 but sum=2.5 which equals N.

Keep practicing — related questions