Subject: General Aptitude · Chapter: Problems on Numbers · Exam: · Marks: · Difficulty:
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?
(a)4
(b)8
(c)16
(d)None of these
Answer
Answer (as printed): B
Explanation
Since the number is greater than the number obtained on reversing the digits, so the ten's digit is greater than the unit's digit. Let the ten's and unit's digits be $2 x$ and $x$ respectively. Then, $(10 \times 2 x+x)-(10 x+2 x)=36 \Leftrightarrow 9 x=36 \Leftrightarrow x=4$. ∴ Required difference $=(2 x+x)-(2 x-x)=2 x=8$.
Explanation as extracted from the printed page; notation may be imperfect.