Answer:
In this case you have 50% solution, so it is 1/2 pure stuff and 1/2 other stuff.
You have 4 gallons, so the include 2 gallons of pure stuff and 2 gallons of other stuff (perhaps water).
You need 60% mixture.
And you have pure stuff to add.
So,
x = amount of pure stuff to add
50%(4) + 100%(x) = 60%(4+x)
Notice the final volume is 4+x.
.5(4) + 1(x) = .6(4) + .6(x)
multiply by 10 to eliminate decimals
5(4) + 10x = 6(4) + 6(x)
20 + 10x = 24 + 6x
4x = 4
x = 1
This suggests you add 1 gallon of pure stuff to 4 gallons of 50% mixture to end up with 5 gallons of 60% mixture.
Always check your solution.
5 * 60% = 3 gallons of pure stuff and 2 gallons of water.
4 * 50% = 2 gallons of pure stuff
1 * 100% = 1 gallon of pure stuff.
Correct!
Answer: Add 1 gallon of pure stuff.
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Step-by-step explanation:
