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Question

5.) A 50 gallon barrel (full) contains an unknown alcohol solution from the 17 hundreds. Per the old incomplete records this solution was achieved by mixing 30 gallons of a 100% solution with a 75% solution. What is the % of the unknown solution and how many gallons of 75% solution were used.

Answer 1

If 30 of the 50 gallons was 100% then 20 gallons were 75%.

30 + 0.75(20) = x(50

30 + 15 = x(50)

45 / 50 = x

90%