SOLUTION: 3. How many kilograms of pure salt must be added to 7 kg of a 30% salt solution in order to produce a 60% solution? Remember that pure salt is a 100% solution of salt. Round you

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Question 619791: 3.
How many kilograms of pure salt must be added to 7 kg of a 30% salt solution in order to produce a 60% solution? Remember that pure salt is a 100% solution of salt. Round your answer to the nearest tenth.
I used the equation (%1)(A1)+(%2)(A2) = (%M)(A1)
I keep getting the wrong answers
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

How many kilogramshighlight%28x%29 of pure salt must be added to 7 kg of a 30% salt solution 

in order to produce a 60% solution?

  salt  = salt

(%1)(A1)+(%2)(A2)  Yes! that part is correct.  

Note: 100% = 1.00

  1· x + .30·7kg = .60(x+7)   ||Note:  need to same 'kgs' on each side of EQ

Solving for x:

  1· x + .30·7kg = .60x+ .60·7kg

      .4x = .30·7kg

        x = .30·7kg/.4 = 5.25kg of pure salt