Find the amount of a 11% saline solution a lab assistant should add to 100 cc of a 21% saline solution in order to have 16% solution

Question

solve the system of equations, basic setup for the question

Answer 1

we have to add 100 cc of 11% saline solution to the 100 cc of 21% saline solution to get a slution of 16%.

we will have a 200 cc solution containing 11 + 21 = 32 cc of saline. that means that in a solution of

200/2=100 cc , we will have. 32/2=16 cc of saline this is a 16% solution