Question

A drum of kerosene oil is $\frac{3}{4}$ full. When $15$ litres of oil is drawn from it, it is $\frac{7}{12}$ full. The capacity of the drum is _____ .

• A. $45$ litres
• B. $90$ litres
• C. $60$ litres
• D. Can't be determined

Answer 1

Answer: (B)

$90$ litres

Let capacity of drum $=x$ litres.

Initially, the drum was $\frac{3x}{4}$ part filled. When $15$ litres oil drawn then it becomes $\frac{7x}{12}$ part.

Now, according to question,

$\frac{3x}{4}$$-\frac{7x}{12}=15$

$\frac{9x-7x}{12}=15$

$2x=180$

so, $x=90$ litres. Hence, B is right option.