One canned juice drink is 25​% orange​ juice; another is 5​% orange juice. How many liters of each should be mixed together in order to get 20L that is 6​% orange​ juice?

1 Answer
Jul 26, 2018

1 liter of the 25% orange juice and 19 liters of the 5% orange juice should be mixed together.

Explanation:

With these types of problems, I like to draw a visual to help plan out the equation first.
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Here we're adding some amount of 25% orange juice to 5% orange juice to get 6% orange juice. We don't know how much of each at first, but we do know that they have to add up to 20 liters. That means we can write the amount of liters of each orange juice as #x# and #20-x#.

Now we just translate this into an equation:

#(0.25)(x) + (0.05)(20-x) = (0.06)(20)#
#0.25x + 1 - 0.05x = 1.2#
#0.2x = 0.2#
#x = 1#

Plugging this back into our visual, we see that we use
#1# liter of 25% orange juice and
#19# liters of 5% orange juice.