SOLUTION: what are the rules divisible by 7 and it's numbers which can be divisible

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Question 484804: what are the rules divisible by 7 and it's numbers which can be divisible
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

take the last digit, double it, and subtract it from the rest of the number;
if the answer is divisible by 7 (including 0), then the number is also.
ex:
the number is 861

ake the last digit 1, double it (2) , and subtract it from the rest of the number 86-2=84
the 84 is divisible by 7...->84%2F7=12 (including 0),
then the number 861 is also divisible by 7
861%2F7=123