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 140 ounces of a mixture that is 85 % salt How many ounces of each solution should she use?

Answer 1

Given:

a.) Solution A is 65% salt

b.) Solution B is 90% salt

c.) She wants to obtain 140 ounces of a mixture that is 85% salt.

Let x = the number of ounces of Solution A

Let y = the number of ounces of Solution B

x + y = 140

y = 140 - x (Eq. 1)

0.65x + 0.90y = 0.85(140)

0.65x + 0.90y = 119

(0.65x + 0.90y = 119) x 100

65x + 90y = 11,900 (Eq. 2)

Substitute Eq. 1 to Eq. 2

65x + 90y = 11,900

65x + 90(140 - x) = 11,900

65x + 12,600 - 90x = 11,900

65x - 90x = 11,900 - 12,600

-25x = -700

-25x/-25 = -700/-25

x = 28 ounces

y = 140 - x

y = 140 - 28

y = 112 ounces

Therefore, you will be needing 28 ounces of Solution A and 112 ounces of Solution B.