Carcass wrote:
A solution is made up of 13 parts water, 2 parts orange juice, and 4 parts apple juice. If you wanted the percentage of orange juice to be 25% of the solution, how many parts would you need to add?
PRESENT volume = 13 parts + 2 parts + 4 parts = 19 parts
Let x = the number of parts of orange juice to be added.
So,
x + 2 = volume of orange juice in RESULTING solution
And,
19 + x = volume of RESULTING solution
We want the RESULTING solution be 25% orange juice
So, we can write: (
x + 2)/(
19 + x) = 25%
Rewrite as: (
x + 2)/(
19 + x) = 1/4
Cross multiply to get: 4(x + 2) = 1(19 + x)
Bing: 4x + 8 = 19 + x
Bop: 3x + 8 = 19
Blam: 3x = 11
Boom: x = 11/3
Answer: 11/3
Cheers,
Brent