Question

A rectangular piece of metal with sides $24cm$ and $18cm$ costs $Rs.1080$. How much will a square piece of the same metal of side $16cm$ cost if the cost of metal is proportional to its area.

• A. $Rs.840$
• B. $Rs.640$
• C. $Rs.720$
• D. $Rs.900$

Answer 1

The correct option is B $Rs.640$

Given,

length of the rectangle $=24cm$

breadth of the rectangle $=18cm$

each side of the square $=16cm$

Area of the rectangle$=24\times 18c{m}^2=432c{m}^2$

Area of the square $=16\times 16c{m}^2=256c{m}^2$

Given, rectangular piece of metal cost $Rs.1080$

Let, the price of the square piece be $Rs.x$

ATQ,

$\frac{x}{1080}=\frac{256}{432}$

$\Rightarrow x=\frac{256\times 1080}{432}$

$\Rightarrow x=640$

Hence, the price of the square piece is $Rs.640$.