1984 AMC 12 Problem 3
Attempt Problem 3 of the 1984 AMC 12 below, then check your answer against the professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 1984 AMC 12 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
3.
Let be the smallest nonprime integer greater than with no prime factor less than Then
Answer: C
Small hint:
The smallest permitted prime factor is
Big hint:
To make the smallest composite, use the two smallest permitted prime factors
Solution:
Every prime factor of is at least The smallest composite with that property is which lies in
Therefore, the correct answer is C.
Problem 3 in other years
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