Question : The 2 digit number which becomes (5/6)th of itself when its digits are reversed. The difference in the digits of the number being 1, then the two digits number is
a) 45
b) 54
c) 36
d) None of these.
Doubt by Pushkar
Solution :
This question can be solved by traditional methods also by forming two different linear equations and then solving those equations by using elimination method. But since it is an MCQ so we will try to solve it making the use of given options.
It is given that the two digits are differ by 1. As we can see that digit in all first three options are differ by 3 so it's not quite useful. Lets use the first condition.
Reverse Number = (5/6) × Original Number
Let's try the first option
Original Number = 45
Clearly
Reverse Number ≠ (5/6)×45 = 37.5
Hence, a) would not be the correct option.
Let's move to the second option
Original Number = 54
Clearly
Reverse Number = (5/6)×54 = 45
45 is the reverse of 54
Hence, b) would be the correct option.