SOLUTION: A liter of fluid is 50% alcohol. How much water must be added to dilute it to a 20% solution? my work: so x is the amount of water to be added. so something + x shou

Question 154167This question is from textbook college algebra
: A liter of fluid is 50% alcohol. How much water must be added to dilute it to a 20% solution?

my work: so x is the amount of water to be added.
so something + x should = .20?? This question is from textbook college algebra

Answer by orca(409) (Show Source): You can put this solution on YOUR website!
The following fact is used to set up the equation:
The amount of the pure alcohol before mixing must be equal to the amount of the pure alcohol after mixing.
So
*****************************************************
The solution before mixing: 1L of 50% solution
The amount of alcohol before mixing is 50%*1
*****************************************************
The solution after mixing: 1+x liters of 20% solution
The amount of alcohol after mixing is 20%*(1+x)
*****************************************************
So the equation is:
50%*1 = 20%(1+x)
Solving for x, we have
50 = 20(1+x) (multiply both sides by 100)
50 = 20 + 20x
30 = 20x
30/20 = x
1.5 = x

RELATED QUESTIONS
How much water must be added to 20 gallons of a solution that is 30% alcohol to dilute it (answered by ewatrrr)

how much water must be added to 45 liters of a solution that is 10% alcohol to dilute it... (answered by josgarithmetic)

ten fluid ounces of a fruit drink is 90% juice. how many fluid ounces of water must be... (answered by drk)

Please help me solve the following: a 12 liter antifreeze solution is made up of water... (answered by lwsshak3)

you have a 40 liter solution that is 90% alcohol. How many liters of water must be added... (answered by josgarithmetic)

How much water must be added to a 20 quarts of a 12% alcohol solution to dilute it to a... (answered by stanbon,modi.kk91)

How much water must be added to 20 quarts of a 12% alcohol solution to dilute it to a 9%... (answered by lwsshak3)

How many quarts of water must be added to 18 quarts of 32% alcohol solution to dilute it... (answered by ankor@dixie-net.com)

How much water must be added to 120 mL of a 35% alcohol solution to dilute it to a 25%... (answered by mananth)