Question

In a chemistry lab, there is some quantity of 50% acid solution and some quantity of 25% acid solution. How much of each should be mixed to make 10 litres of 40% acid solution?

Answer 1

Let taking x litres quantity of 50% acid solution
and y litres quantity of 25% acid solution.

Given, After mixing both types of acid.

Solution, The total quantity is 10 litres.

Therefore, x + y = 10      ...(i)

According to the question,     

`50/100x + 25/100y = 40/100 xx 10`

⇒ `x/2 + y/2 = 4`

2x + y = 16      ...(ii)

On subtracting eq. (i) from eq. (ii)

x = 6 litres

Put x = 6 in eq. (i) to get y

6 + y = 10

y = 10 − 6

⇒ y = 4 litres

Hence, we should take 6 litres from 50% Acid solution and 4 litres from 25% Acid solution.