Number theoryDifficulty 3.9AMC 10/12Find the answer
Let N be the least positive integer that is both 22 percent less than one integer and 16 percent greater than another integer. Find the remainder when N is divided by 1000.
A number or a short expression. Spacing and $ signs are ignored.
Solution
If N is 22 percent less than one integer k, then N=10078k=5039k. In addition, N is 16 percent greater than another integer m, so N=100116m=2529m. Therefore, k is divisible by 50 and m is divisible by 25. Setting these two equal, we have 5039k=2529m. Multiplying by 50 on both sides, we get 39k=58m. The smallest integers k and m that satisfy this are k=1450 and m=975, so N=1131. The answer is 131.
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