Question

Seats for Mathematics, Physics and Biology in a school are in the ratio 5:7:8. There is a proposal to increase these seats by 40$\%$, 50$\%$ and 75$\%$ respectively. What will be the ratio of increased seats?

• A. 2:3:4
• B. 2:3:5
• C. 5:6:8
• D. 3:6:8

Answer 1

The correct option is A

2:3:4

Originally, let the number of seats for Mathematics, Physics and Biology be 5x, 7x and 8x respectively.

After increase, the number of seats are (140$\%$ of 5$x$), (150$\%$ of 7$x$) and (175$\%$ of 8$x$).

$\to$ $\frac{140}{100}$ $\times$ 5$x$, $\frac{150}{100}$ $\times$ 7$x$, $\frac{175}{100}$ $\times$ 8$x$

$\to$ 7$x$, $\frac{21x}{2}$, 14$x$

$\therefore$ The required ratio = 7$x$:$\frac{21x}{2}$:14$x$

$\to$14$x$ : 21$x$ : 28$x$

$\to$ 2 : 3 : 4