Question

Charlie mixes 15 liters of 17% acid solution with a 29% acid solution, which results in 23% acid solution.

Let x represent the number of liters of 29% solution used and let y represent the number of liters of mixture. Which system of equations can be used to find the number of liters of 29% acid solution in the mixture

Answer 1

(15(.17)+.29x)/(15+x)=.23

2.55+.29x=3.45+.23x

.06x=.9

x=15

So 15L of the 29% solution was added to the 15L of 17% solution to make
30L of 23% solution.

Answer 2

The number of liters of 29% acid solution is 15

Explanation:

Let x represent the number of liters of 29% solution

Let Y represent the number of liters of mixture

Charlie mixes 15 liters of 17% acid

Resulting solution of acid = 23%

29x+0.17(15)= 0.23(15+x)

Then

29x+2.55=3.45+0.23

29x - 0.23x=3.4 - 2

6x =0.9

x=15

Therefore the number of liters of 29% acid solution is 15