Question

In a two digit number the tens digit is three times the unit digit.when the number is decreased by 54, the digit are reversed. Find the numbers

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 = 3y ------------1

Also given:

10x + y – 54 = 10y + x

9x – 9y = 54

x – y = 6 -------------2

substitute the value of x from equation 1 in equation 2

3y – y = 6

2y = 6

y = 3

Therefore, x = 3 * y = 3 * 3 = 9

Therefore, the two-digit number = 10x + y = (10*9) + 3 = 93

and the reversed number = 10y + x = (10 *3) + 9 = 39