SOLUTION: How much salt must be added to 60 kg of a 20% solution of salt to increase it to 25% solution of salt ?

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: How much salt must be added to 60 kg of a 20% solution of salt to increase it to 25% solution of salt ?      Log On


   

Question 804056: How much salt must be added to 60 kg of a 20% solution of salt to increase it to 25% solution of salt ?
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Let y = the amount of salt to add to change to 25%.

Amount of salt just as salt, 60%2A0.20%2By.
Amount of salt solution result, 60%2By.

If 25% salt result is wanted, then %2860%2A0.20%2By%29%2F%2860%2By%29=0.25

Steps:
12%2By=0.25%2860%2By%29
12%2By=15%2By%2F4
48%2B4y=60%2By
48%2B3y=60
3y=60-48=12
ANSWER: y=4 kg.


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You can set-up the solution for values of resulting salt solution higher than 25%, but beyond 25% salt solution would not be realistic. Certainly anything as high as 40% will NOT happen, although you CAN set the initial equation for it and do the algebra/arithmetic steps similarly as shown.