Question 1133987
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Given two positive integers a and b that are relatively prime, the largest sum that cannot be made using multiples of a and b is the product of the two integers, minus the sum of the two integers: (ab)-(a+b).<br>
For this problem, with the integers 8 and 15, the largest sum that cannot be made is (8*15)-(8+15) = 120-23 = 97.