Divisibility by 7
Subtract twice the last digit from the no. formed by the remaining digits.
EG: Is 651 divisible by 7
65-(1x2)=63 is divisible by 7 so 651 is also divisible by 7
Divisibility by 11
Make alternate pairs of digits in the no. from right side add both pairs separately and subtract the sum of both pairs the answer should be 0 or a multiple of 11.
EG: Lets check the divisibility of 396 by 11
396 6+3=9
9+0=9
9-9=0
So , 396 is divisible by 11
Best Regards and hope this helps u
Poorva
