Assistance Please

Question

A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains salt. She knows that Solution A is 30% salt and Solution B is 90% salt. She wants to obtain 40 ounces of a mixture that is 45% salt. How many ounces of each solution should she use?

Answer 1

x represents the amount of 90%

40 - x represents the amount of 30%

0.90x + 0.30(40 - x) = 0.45(40)

Can you solve for x and answer?