Question

PLEASE HELP ME ;-;

Amy mixes 12 liters of 16% acid solution with a 40% acid solution, which results in 32% acid solution.

Let x represent the number of liters of 40% 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 40% acid solution in the mixture?






y = x + 12; 0.4y = 0.32x + 3.84

y = x + 12; 0.4y = 0.32x + 1.92

y = x + 12; 0.32y = 0.4x + 4.8

y = x + 12; 0.32y = 0.4x + 1.92

Answer 1

x+12=y  - number of liters when solutions are mixed
0.4x - amount of acid in 40% solution
12 *0.16=1.92 - amount of acid in 12 L of 16% solution
0.4x+1.92 - amount of acid when solution are mixed
0.32y - amount of acid that we want to get , is the same as amount of acid when solutions are mixed,
so second equation is 0.32y=0.4x+1.92,
 so correct answer is last one D