What's the answer

Question

1.     A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains 30% salt. She knows that Solution A is 90% salt and Solution B is salt. She wants to obtain 120 ounces of a mixture that is 35% salt. How many ounces of each solution should she use?

Solution A:

Solution B:

Answer 1

30X + 90(120-X) = 120(35)

30X-90X = 4200-10800

60X = 6600

X = 110 ounces of 30% mixed with

120-110 = 10 ounces of 90% to yield 120 ounces of 35%

30 is within 5 of 35

90 is within 55 of 35

55 is 11 times 5

110 is 11 times 10