Question

The sum of a two digit number is 7. When the digits are reversed and the number is decreased by three, it becomes 4 times the original number. Find the original number.

Answer 1

Step-by-step explanation:

Let the one's digit number = x

Sum = 7

Tens digit number = 7 - x

So, the number becomes = 10(7 - x)+x = 70 - 9x

Reversed Number = 10x + 7

A/q,

Now, If the number is revered, then the number is decreased by 3

Revered Number = 10x + (7 - x) = 10x + 7 - x = 9x + 7

Reverse Number - 3 = 4(Original number)

9x + 7 - 3 = 4(70 - 9x)

9x + 4 = 280 - 36x

9x + 36x = 280 - 4

45x = 286

x = 286/45