Is a 3-digit number divisible by 6?
1). The sum of tens' and hundreds' digit is 6
2). The units' digit is 6
Neither statement is sufficient alone, clearly. Together:
-the sum of the digits is 12, so the number is divisible by 3
-the units digit is even, so the number is even, and thus divisible by 2
Since the number is divisible by both 2 and 3, it must be divisible by the LCM of 2 and 3, which is 6. C.
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