Answer:
The nurse should use 200cc of the 10% saline solution in order to produce a 20% saline solution.
Step-by-step explanation:
to the given mix we add a quantity of a lower mix to generate another.
50cc at 60% + Xcc at 10% = (50 + X)cc at 20%
50 x 60% + X x 10% = (50 + X) x 20%
30 + 0.1X = 10 + 0.2X
30 - 10 = 0.2X - 0.1X
20 = 0.1X
20/0.1 = X
X = 200
