Question

A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains salt. She knows that Solution A is 65% salt and Solution B is 90% salt. She wants to obtain 180 ounces of a mixture that is 80% salt. How many ounces of each solution should she use?

Answer 1

72 ounces of Solution A

108 ounces of Solution B

Explanation:

If a is ounces of Solution A, and b is ounces of Solution B, then the total amount is:

a + b = 180

The total amount of salt is:

0.65a + 0.90b = 0.80(180)

Substitute:

0.65a + 0.90(180 − a) = 0.80(180)

0.65a + 162 − 0.90a = 144

0.25a = 18

a = 72

b = 108