Question

How much 9% saline solution should be mixed with 80 Cc of a 17% saline solution to produce a 13% saline solution?

Answer 1

80 cc.

Explanation:

We work in amounts of salt in the solutions:

0.09x + 0.17*80= 0.13(x+ 80) where x is the required volume of 9% solution.

0.09x + 13.6 = 0.13x + 10.4

13.6 - 10.4 = 0.13x - 0.09x

3.2 = 0.04x

x = 3.2 / 0.04

x = 80