Problema Solution

A dehydrated patient needs a 6.8% saline IV. Unfortunately, the hospital only has bags of 2% and 8% saline solutions. How many liters of each of these solutions should be mixed together to yield 2 liters of the desired concentration?

Answer provided by our tutors

Let x = amt of 8% solution required

the resulting amt is to be 2 liters, therefore

(2-x) = amt of 2% solution required

:

Write a decimal form of the amt of saline equation

:

.08x + .02(2-x) = .068(2)

.08x + .04 - .02x = .136

.08x - .02x = .136 - .04

.06x = .096

x = 

x = 1.6 liters of the 8% solution

2 - 1.6 = .4 liters of the 2% solution