The integer 119 is a multiple of which number?
Solution
The ones digit of 119 is not even, so 119 is not a multiple of 2. The ones digit of 119 is not 0 or 5, so 119 is not a multiple of 5. Since , then 119 is 1 less than a multiple of 3 so is not itself a multiple of 3. Since and , then 119 is between two consecutive multiples of 11, so is not itself a multiple of 11. Finally, , so 119 is a multiple of 7.
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