One canned juice drink is 15% orange juice; another is 5% orange juice. How many liters of each should be mixed together in order to get 10 L that is 14% orange juice?

1 Answer
Dec 18, 2016

9 liters of 15% orange juice and 1 liter of 5 % orange juice.

Explanation:

Let x be the number of liters of 15% juice, and
y be the number of liters of 5% juice.

Then x + y = 10

and 0.15x + 0.05y = 1.4

(there are 1.4 liters of orange juice in a 14% solution of 10 liters--made up of 0.15x liters of 15%, and 0.05y of 5%)

These equations can be easily solved.

Divide the second by .05" "rarr: 3x + y = 28
Then subtract the first equation:

(3x + y) - (x + y) = 28 - 10
3x +y -x -y = 18

which simplifies to 2x = 18

So x =9

And since x + y = 10, we get y = 1