Question

If a nine-digit number 785x3678y is divisible by 72, then the value of (x −
y) is:

Q: Answer-If a nine-digit number 785x3678y is divisible by 72, then the value of (x − y) is:

The nine digit number is 785x3678y is divisible by 72, so we can say number also divisible by 8 and 9. 785x3678y is divisible by 8 if last digit three digit 78y is divisible by 8. 78y is divisible by 8 if y 4 785x36784 is divisible by 9 if the sum of its digit is divisible by 9. 7 8 5 x 3 6 7 8 4 48 x Put x 6 48 6 54 As we know, 54 is divisible by 9. Now, x y 6 - 4 2