.How many liters of a 12% and 33% alcohol solution must be mixed to obtain 21 liters of a 25% solution?

What amount of pure acid must be added to 500 ml of a 25% acid solution to produce a 50% acid solution?

How much of 70% alcohol and how much of 20% alcohol are needed to make a 30% solution?

How many gallons of a 35% solution should be mixed with 7 gallons of a 60% solution to create a 50% solution?

How many liters of 20 alcohol solution should be added to 40 liters of a 50?

How many liters of 20% solution should be added to 40 liters of a 50% solution to make a 30% solution?

How many liters of a 10% acid solution must be mixed with 101 of a 4% solution to obtain a 6% solution?

How many gallons of hydrochloric acid must be added to 12 gallons of a 30% solution to obtain a 40% solution?

How many Litres of a mixture containing 80% alcohol should be added to 5 Litres of a 20% solution to yield a 30% solution?

How much of a 20% acid solution would a chemist have to mix with 1000 ml of a 40% acid solution to yield a 36% acid solution?