Question 66951: Florence Flask has 500 grams of a 72% salt solution. How much water must she add to obtain a 25 % salt solution? Answer by ptaylor(2198) (Show Source):
You can put this solution on YOUR website!
Let x=amount of water to be added
Now we know that the amount of pure salt in the solution before the water is added (.72)(500) is equal to the pure salt in the solution after the water is added (.25)(500+x). So our equation to solve is:
(.72)(500)=(.25)(500+x) get rid of parens by multiplying out:
360=125+.25x subtract 125 from both sides
360-125=125-125+.25x
235=.25x divide both sides by .25
x=940 grams----------------amount of water to be added
CK
500(.72)=.25(500+940)
360=.25(1440)
360=360
