2011 AMC 12B Problem 5
Below is the professionally curated solution for Problem 5 of the 2011 AMC 12B, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2011 AMC 12B solutions, or check the answer key.
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Difficulty rating: 990
5.
Let be the second smallest positive integer that is divisible by every positive integer less than What is the sum of the digits of
Solution:
A number divisible by every integer from to must be a multiple of
The second smallest positive multiple of is whose digit sum is
Thus, the correct answer is A.
Problem 5 in Other Years
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