Question

If the 9-digit number 5y97405x2, is divisible by 72,

Q: Answer-If the 9-digit number 5y97405x2, is divisible by 72, find the value of (x – 2y) for the greatest val...

For the number 5y97405x2 to be divisible by 72 Divisibility by 8 Last three digits 5x2 must be divisible by 8. For x 4, 542 is divisible by 8. Divisibility by 9 Sum of digits 36 y must be divisible by 9. For y 0, 36 is divisible by 9. Thus, with x 4 and y 0, x - 2y 4 - 20 4.