The difference between a two-digit number and the number obtained by interchanging the positions of its digits is 36. What is the difference between the two digits of that number?
Select the correct option:
A) 4
B) 5
C) 6
D) 8
E) 9
Sol.   Let the ten’s digit be x and unit’s digit be y,   Then, (10x + y) - (10y + x) = 36 ⇔ 9 (x - y) = 36   ⇔ x - y = 4   4nswer 4
<result>A</result>
The difference between a two-digit number and the number obtained by interchanging the positions of its digits is 36. What is the difference between the two digits of that number?