document.write( "Question 253228: how much water must be added to 12 grams of a 90% acid solution to produce a 25% acid solution? \n" ); document.write( "
Algebra.Com's Answer #185499 by drk(1908)\"\" \"About 
You can put this solution on YOUR website!
This is a mixture problem. Here is the table based on the information given. Remember that water is 0% acid.
\n" ); document.write( "solution . . . . .% . . . . . gram . . . . . %gram
\n" ); document.write( "acid . . . . . . .90 . . . . .12 . . . . . . .1080
\n" ); document.write( "water . . . . . . 0 . . . . . .X . . . . . . .0
\n" ); document.write( "mixture . . . . . 25 . . . . .12 + X . . . . .300 + 12X
\n" ); document.write( "We can now set
\n" ); document.write( "1080 + 0 = 300 + 12X.
\n" ); document.write( "Solving for X< we get
\n" ); document.write( "780 = 12X
\n" ); document.write( "X = 65 grams of water. \n" ); document.write( "
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