2011 AMC 8 Problem 24
Attempt Problem 24 of the 2011 AMC 8 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 2011 AMC 8 solutions, or check the answer key.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
24.
In how many ways can be written as the sum of two primes?
Small hint:
Check whether is prime.
Big hint:
An odd sum of two primes must include the only even prime.
Solution:
For two numbers to add to an odd number, one of them must be odd and the other even. Thus the only even prime is so the other number is forced to be is not prime, however, so cannot be written as the sum of two primes.
Thus, A is the correct answer.
Problem 24 in other years
- 1985 AMC 8
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