Subject: General Aptitude · Chapter: Ratio and Proportion · Exam: · Marks: · Difficulty:
In a class the number of girls is 20\% more than that of the boys. The strength of the class is 66. If 4 more girls are admitted to the class, the ratio of the number of boys to that of the girls is
(a)1 : 2
(b)1 : 4
(c)3 : 4
(d)3 : 5
Answer
Answer (as printed): C
Explanation
Let the number of boys be $x$. Then, number of girls $$\begin{aligned} & =120 \% \text { of } x=\frac{6 x}{5} . \\ \therefore & x+\frac{6 x}{5}=66 \Rightarrow \frac{11 x}{5}=66 \Rightarrow x=\frac{66 \times 5}{11}=30 . \end{aligned}$$ So, number of boys $=30$. And, new number of girls $$=\left(\frac{6 \times 30}{5}\right)+4=40 .$$ ∴ Required ratio $=30: 40=3: 4$.
Explanation as extracted from the printed page; notation may be imperfect.