Question

Confused? Percentages?

Answer 1

Hint: simultaneous equations

Answer 2

What? D:

Answer 3

I don't need just the answer but a walkthrough would help!

Answer 4

You know x+y = 51 (total amount of solution)
How do you state 30% solution of acid in terms of x and y?

Answer 5

but i have to add two different substances with different solutions of acid, don't they add up to more than 30%?

Answer 6

Well, no, even if you used all of the 40% solution, your acid could never be stronger than 40%.

Answer 7

So i add mostly 25% and a much smaller amount of the 40% to make the 30%?

Answer 8

Correct!!! The total strength will be (.25x+.40y)/(x+y) [the weighted average of x and y]

Answer 9

would it be 46 and 5?

Answer 10

40x + 25 ( 51 - x) = 30 * 51
@JulietteAllisonn Can you solve it from here?

Answer 11

46 and 5 gives me a strength of 26.47% unless I'm doing the math wrong?