Question

9. How many gallons of 5% acid solution should be
mixed with 20 gallons of a 10% acid solition to obtain
an 9% acid solution? (The gallon is a unit of
measurement for volume and fluid capacity)
B) 6
A) 5
D) 8
C) 7​

Answer 1

Step-by-step explanation:

If you add X gallons of 5% acid solution you add .05x acid.

There is .1(20)=2 gallons of acid in 20 gallons of 20% solution.

So so the concentration of the new solution can be calculated as (.05x+2)/(20+X) =.06

cross mutiply and simplify

.05x+2=1.2+.06x

.8=.01x

X= 80 gallons.

Checking,

if we add 80 gallons of 5% solution we are adding 4 gallons of acid to the original 2 gallons of acid to be 6 gallons and 6/100 gallons (20 we started w +80 we added) is a 6% solution.

Hope it helps you mate..

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