If a number is reduced by 40\% it becomes twothirds of another number. What is the ratio of the first number to the second number?
(a)8: 9
(b)9: 8
(c)10: 9
(d)9: 10
(e)None of these
Answer
Answer (as printed): C
Explanation
Let the numbers be $x$ and $y$ respectively. $$\text { Then, } \begin{aligned} 60 \% \text { of } x=\frac{2}{3} y & \Rightarrow \frac{60}{100} x=\frac{2}{3} y \Rightarrow \frac{3}{5} x=\frac{2}{3} y \\ & \Rightarrow \frac{x}{y}=\frac{2}{3} \times \frac{5}{3}=\frac{10}{9} \end{aligned}$$
Explanation as extracted from the printed page; notation may be imperfect.