Question

If a tap can fill a cistern of 20 litres in 2 minutes, then how long will it take to fill a tank of capacity 2,000 litres?

• A. 200 mins
• B. 250 mins
• C. 220 mins
• D. 180 mins

Answer 1

The correct option is A 200 mins

Given,
time taken to fill a cistern of capacity 20 litres is 2 mins.

We know that the larger is the capacity, the more will be the time taken by the tap to fill it.

$\text{Capacity}\left(x\right)\propto \text{Time taken}\left(y\right)$
$\therefore \frac{x_1}{y_1}=\frac{x_2}{y_2}$

Given,
$x_1=20litres$
$y_1=2mins$
$x_2=2000litres$
$\text{and}{y}_2=\text{time taken to fill the tank}$

$\Rightarrow \frac{20}{2}=\frac{2000}{y_2}$
$\Rightarrow y_2=\frac{2000\times 2}{20}=200mins$

Hence, it will take 200 mins to fill a tank of 2,000 liters.