The difference between a two digit number and the number obtained by interchanging the positions of its digits is 36. What is the different between the two digits of that number?
Answer: (3) 4
Let be the unit digit is X and ten digit is Y
According to question, (10Y + X) – (10X – Y) = 36
9Y – 9X = 36
9(Y – X ) = 36
Y – X = 36/9
Y – X = 4
Hence, the difference between required numbers is 4.