Question

the sum of a two digit number is 8 and the difference between the number and that formed by reversing the digit is 18. Find the number.

Answer 1

Let the digits be a and b.
So, a+b=8
Now the number is ab and that which is formed by reversing it is ba
Given,
ab-ba=9(a-b)
So, 9(a-b) = 18 ( given)
or, a-b = 18/9 = 2
Now, a+b+a-b = 8+2
a+a = 10 ( As b is cancelled out)
or, 2a = 10
or, a= 10/2 = 5
Now, given, a+b =8
or, b= 8-5 = 3