Question

The sum of two digit number is 12 The number obtain by reversing the digit exceed the given number by 18 Find the number

Answer 1

Let the digit be ab. Then a+b =12, and 10a+b=10b+a + 18, upon simplifying you will get b-a=2, upon further simplifying the first and last equation you will get a=5, and b=7, therefore the number is 57