Question

A tin contains a mixture of two liquids A and B in the proportion 4: 1. If 35 litres of the mixture is replaced by 35 litres of liquid B, then the ratio of the two liquids becomes 1: 2. How much of the liquid B is there in the tin now?

• A. 35 L
• B. 42 L
• C. 40 L
• D. 45 L

Answer 1

The correct option is C 40 L

Let us say there were 4x litres of liquid A and x litres of liquid B. Now if you remove 35 litres from this, It will be $\frac{4}{5}\times 35=28$ litres of liquid A and 7 litres of liquid B
Now, to this we are adding 35 litres of liquid B. So, the new ratio is:
$4x-28:x+28=1:2\Rightarrow 2(4x-28)=x+28$
We get, x = 12 Kg.
Amount of liquid B in the solution = 12+28 = 40 L.