Subject: General Aptitude · Chapter: Problems on Numbers · Exam: · Marks: · Difficulty:
The sum of two numbers is 40 and their difference is 4 . The ratio of the numbers is
(a)11 : 9
(b)11 : 18
(c)21 : 19
(d)22 : 9
Answer
Answer (as printed): A
Explanation
Let the numbers be $x$ and $y$. Then, $\frac{x+y}{x-y}=\frac{40}{4}=10 \Leftrightarrow(x+y)=10(x-y)$ $$\Leftrightarrow \quad 9 x=11 y \Leftrightarrow \frac{x}{y}=\frac{11}{9} .$$
Explanation as extracted from the printed page; notation may be imperfect.