A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains salt. She knows that Solution A is 60% salt and Solution B is 85%

Question

A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains salt. She knows that Solution A is 60% salt and Solution B is 85% Salt. She wants to obtain 180 ounces of a mixture that is 75% salt. How many ounces of each Solution should she use 

Answer 1

Let x = the number of ounces of Solution A

Let y = the number of ounces of Solution B

x + y = 180        y = 180 - x

.60x + .85y = .75(180)

.60x + .85y = 135      Multiply both sides of the equation by 100 to remove the decimal points.

60x + 85y = 13500

60x + 85(180 - x) = 13500

60x + 15300 - 85x = 13500

-25x = -1800

x = 72ounces

y = 180 - 72

y = 108 ounces