The difference between a two digit number and the number obtained by interchanging the digits is 36. What is the difference between the sum and the difference of the digits of the number if the ratio between the digits of the number is 1 : 2?  Choose the correct choice from the following:  A) 4  B) 8  C) 12  D) 16  E) 18
Sol.   Since the number is greater than the number obtained on reversing the digits, so the ten's is greater than the unit's digit.   Let the ten's and units digit be 2x and x respectively.   Then, (10× 2x + x) - (10x + 2x) = 36   ⇔ 9x = 36   ⇔ x = 4.   ∴ Required difference = (2x+x)-(2x-x) = 2x = 8.   Answer 8
<result>B</result>
The difference between a two digit number and the number obtained by interchanging the digits is 36. What is the difference between the sum and the difference of the digits of the number if the ratio between the digits of the number is 1 : 2?