Answers

2015-05-06T21:29:14+05:30
There are no rules of divisibility for 7.
0
2015-05-06T21:48:33+05:30
Take the last digit of the number you're testing and double it. Subtract this number from the rest of the digits in the original number. If this new number is either 0 or if it's a number that's divisible by 7, then you know that the original number is also divisible by 7
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