The ratio of petrol and kerosene in the container is 3:2 when 10 liters of the mixture is taken out and is replaced by the kerosene, the ratio become 2:3. Then total quantity of the mixture in the container is:

• A. 25
• B. 30
• C. cannot be determined
• D. 45

Answer: (B)

pool : kerosene     3  :  2(initially)     2  :  3(after replacement)     R e m a i n i n g   Q u a n t i t y I n i t i a l   Q u a n t i t y = 1 - R e p l a c e d   Q u a n t i t y T o t a l   Q u a n t i t y   (for petrol)    2 3 = 1 - 10 k  => K = 30  Therefore the total quantity of the mixture in the container is 30 liters.