Question 1127385
let the quantity of 7% solution be x
Then, the quantity of 2% will be 40 - x
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0.07x + 0.02(40-x) = 0.04(40)
0.07x + 0.8 - 0.02x = 1.6
0.05x = 0.8
x = 16 this is the quantity needed of the 7% solution
to be mixed with:
40-16 = 24 gallons of the 2% solution
Happy learning!