A salt solution of 400g is in each container A, B, and C and density in A, B , and C is 16%, 8%, and 4% respectively.
When total of 100g salt solution was taken out of container A and B and it added to container C, the density of container C became 5%.
Find the weight of the salt solution taken out of container A.
Answer
12.5 g
Solution
400g × 4% = 16g
(400g + 100g) × 5% = 25 g
25g - 16g = 9g
9 / 100 = 9%
(16 - 9) : ( 9 - 8) = 7 : 1
Thus the weight of salt solution from A is 100 × 1/(7+1) = 12.5g
