The remainder when 111 is divided by 10 is 1. The remainder when 111 is divided by the positive integer is 6. How many possible values of are there?
Solution
Since the remainder when 111 is divided by is 6, then is a multiple of and (since, by definition, the remainder must be less than the divisor). Since , the positive divisors of 105 are . Therefore, the possible values of are , of which there are 5.
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