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 130 ounces of a mixture that is 70% salt. How many ounces of each solution should she use?
Solution A: ounces

SolutionB: ounces

Answer 1

So let's call x the amount of ounces in Solution A
So then the equation would look something like this.
0.65(x) + 0.9(130-x) = 0.7(130)
To make it easier, multiply both sides by 100:
65(x) + 90(130-x) = 70(130)
multiply.
65x + 11700 - 90x = 9100
Make sure that x is on one side and the numbers are on the other:
-25x = -2600
The negatives cancel out:
25x = 2600
Solve for x:
x = 104.
So then Solution A has 104 ounces, and Solution B has 130 - 104 ounces, which is 26 ounces.
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