Q48 of 244 Page 147

A chemist has one solution containing 50% acid and a second one containing 25% acid. How much of each should be used to make 10 litres of a 40% acid solution?

Let the 50% solution used be x litres


Total volume of solution = 10 litres ( Given )


∴ 25% solution used = (10 - x) litres


Volume of acid in mixture = 40% of 10 litres = 4 litres


but, volume of acid in mixture = 50% of x + 25% of (10 - x)



⇒ x + 10 = 16


⇒ x = 6 litres


Thus, 50% solution = 6 litres and 25% solution = 4 litres.


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