Suppose you add x liters of pure water to the 10 L of 25% acid solution. The new solution's volume is x + 10 L. Each L of pure water contributes no acid, while the starting solution contains 2.5 L of acid. So in the new solution, you end up with a concentration of (2.5 L)/(x + 10 L), and you want this concentration to be 10%. So we have

and so you would need to add 15 L of pure water to get the desired concentration of acid.
Answer:
he has 472 points now.
Step-by-step explanation:
12x > 9(2x-3)-15
distribute the 9
12x > 18x-27 -15
combine like terms on the right side
12x > 18x-42
subtract 18x from both sides
-6x > -42
divide both sides by -6
x = -42 / -6 = 7
x >7
Answer:
I think the answer is D because it doesn't show that the bottom lengths are the same.
Step-by-step explanation: