SOLUTION: how many litres of a 68% alcohol solution must be added to 54 litres of a 38% alcohol solution to produce a 53% alcohol solution?

Question 1149169: how many litres of a 68% alcohol solution must be added to 54 litres of a 38% alcohol solution to produce a 53% alcohol solution?
Found 2 solutions by Alan3354, ikleyn:
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
how many litres of a 68% alcohol solution must be added to 54 litres of a 38% alcohol solution to produce a 53% alcohol solution?
--------------
Add L liters
54*38 + L*68 = (54+L)*53

Answer by ikleyn(52873) (Show Source): You can put this solution on YOUR website!
.

Notice that 53% is exactly half-way between 38% and 68%.

Therefore, as any house-wife will answer you (without solving any equation), you need use 54 liters of the 68% solution.

RELATED QUESTIONS
How many litres of 70% alcohol needs to be added to 50litres of 40% alcohol to make a 50% (answered by richwmiller)
How many litres of a 10% alcohol solution should be mixed with 12 litres of a 20% alcohol (answered by josgarithmetic)
How many litres of pure alcohol must be added to 20 litres of a 50% alcohol concentration (answered by richwmiller)
a solution of 150 litres contains 40% alcohol. how many litres of liquid should be added... (answered by FrankM)
How many liters of a 30% alcohol solution should be added to 40 litres of a 60% alcohol... (answered by josgarithmetic)
How much water must be added to 9 litres of a solution containing 65% alcohol to obtain a (answered by edjones)
How many milliliters of a 29% alcohol solution must be added to 5 milliliters of a 5%... (answered by checkley77)
How many liters of a 70% alcohol solution must be added to 50 liters of a 40% alcohol... (answered by fractalier)
How many milliliters of a 31% alcohol solution must be added to 6 milliliters of a 11%... (answered by Alan3354,Maths68)