Question

a solution of salt and water contains 13% saltby weight. of it 42kg water evaporates and the solution now contains 20% of salt. find original quantity of solution

Answer 1

a solution of salt and water contains 13% saltby weight. of it 42kg water evaporates and the solution now contains 20% of salt. find original quantity of solution

Let, Quantity of original solution = 100x
Then quantity of salt = 13x
when 42 kg of water is evaporated then total quantity = 100x - 42
But quantity of salt will remain same and now quantity of salt is 20% of original quantity
(100x -42) ×1/5 = 13x
= 100x × 0.2 - 42 × 0.2 = 13x
=20x- 8.4 = 13x
=20x - 8.4 -13x = 0
= 7x -8.4 = 0
=7x = 8.4
X = 8.4/7
X = 1.2 kg

this is your answer..