A dehydrated patient needs a 6.4% saline IV. Unfortunately, the hospital only has bags of 6% and 8% saline solutions. How many liters of each of these solutions should be mixed together to yield 1 liter of the desired concentration?

Question

anonymous · Answer

lets call amount of 8% saline $x$ then the amount of 6% saline must be $1-x$ 
you want 
$$.08x+.06(1-x)=.064$$ or more simply 
$$8x+(1-x)=64$$

anonymous · Answer

oops

anonymous · Answer

i think i meant 
$$8x+6(1-x)=6.4$$