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Hi Pat. A common multiple is a number into which both of your numbers The first common multiple of 2 and 5 is 10, because that is the lowest One way of finding the common multiples of 2 and 5 through 30 is to 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30 what's common in these lists? Hope this helps,
 


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