Question

The tens digit of a no. Is twicr its once digit. The sum of the no. By reversing the digit is 99. Find the no.

Answer 1

Let us assume x is a tens digit and y is ones place digit are the two digits of a two digit number

Therefore, the number is 10x + y and reverse number is 10y + x

Given:

x = 2y --------1

Also given:

10x + y + 10y + x = 99

11x + 11y = 99

x + y = 9 -------------2

Substitute the value of x from equation 1 in equation 2

2y + y = 9

3y = 9

y = 3

Therefore, x = 2 * y = 2 * 3 = 6

Therefore, two digit number is = 10x + y = (10 * 6) + 3 = 63