Question

.

How much pure acid should be mixed with 3 gallons of a 20% acid solution in
order to get a 60% acid solution?

Answer 1

3 gallons

Explanation:

Let

x ----> the amount of pure acid (100% solution) in gallons

Remember that

`100\%=100/100=1`

`20\%=20/100=0.20`

`60\%=60/100=0.60`

we know that

`(1)(x)+(0.20)(3)=(0.60)(x+3)`

solve for x

`x+0.60=0.60x+1.80`

`x-0.60x=1.80-0.60\\0.40x=1.20\\x=3\ gal`

therefore

3 gallons of pure acid should be mixed with 3 gallons of a 20% acid solution in order to get a 60% acid solution