Answer:
The answer to the question is;
1.5 gallons of 100% lemon juice added to 2.5 gallons of 20% lemon juice + 80% lime juice to make 4 gallons of the 50% lemon/50% lime juice mixture.
1.5 gallons of 100% lemon juice
Step-by-step explanation:
To solve the question, we note
Desired concentration = 50% lemon juice and 50% lime juice
Available concentration = 100% lemon juice and 20% lemon juice and 80% lime juice
To make 4 gallons of 50% lemon juice and 50% lime juice Milo requires
20 per 100 lemon requires 60 parts of pure lemon to make 160 parts of 50% lemon juice and 50% lime juice
100 requires 60 to make 160
100/160 requires 60/160 to make one part of 50% lemon juice and 50% lime juice
That is 5/8 gallon of 20 % lemon requires 3/8 gallon of pure lemon to make 1 gallon of 50% lemon juice and 50% lime juice
That is 2.5 gallons of 20 % lemon requires 1.5 gallons of pure lemon to make 4 gallons of 50% lemon juice and 50% lime juice
Milo should add 1.5 gallons of 100% lemon juice to 2.5 gallons of a juice mixture that is 20% lemon juice and 80% lime juice to make 4 gallons of the 50% lemon/50% lime juice mixture