2015 AMC 12B Problem 3
Below is the professionally curated solution for Problem 3 of the 2015 AMC 12B, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2015 AMC 12B solutions, or check the answer key.
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Difficulty rating: 1050
3.
Isaac has written down one integer two times and another integer three times. The sum of the five numbers is and one of the numbers is What is the other number?
Solution:
Write If were written twice, then which is not a multiple of
So is written three times: giving
Thus, the correct answer is A.
Problem 3 in Other Years
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