Question 638841
Do it like this one:
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I need 150 gallons of 10% solution but all i have is 5% and 20% solution. How much of the 5% and 20% solution do i need in order ti create 150 gallons of 10% solution?
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t = amount of 20%
f = amount of 5%
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t + f = 150
20t + 5f = 10*150