Subject: General Aptitude · Chapter: Ratio and Proportion · Exam: · Marks: · Difficulty:
The ratio of the arithmetic mean of two numbers to one of the numbers is 3 : 5. What is the ratio of the smaller number to the larger one?
(a)1 : 2
(b)1 : 3
(c)1 : 4
(d)1 : 5
Answer
Answer (as printed): D
Explanation
Let the two numbers be $x$ and $y$. $$\frac{x+y}{2}: x=3: 5 \Rightarrow \frac{x+y}{2 x}=\frac{3}{5} \Rightarrow 5 x+5 y=6 x \Rightarrow x=5 y \Rightarrow \frac{x}{y}=\frac{5}{1} .$$ ∴ Ratio of smaller number to larger number = 1 : 5.
Explanation as extracted from the printed page; notation may be imperfect.