document.write( "Question 215299: a mixture containing 8% salt is to be mixed with 40mL of a mixture that is 20% salt, in order to obtain a solution that is 12% salt. How much of the first solution must be used? \n" ); document.write( "
Algebra.Com's Answer #162669 by RAY100(1637)\"\" \"About 
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Let x = added solution
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\n" ); document.write( ".08x + .2(40) = .12(x+40),,,,,salt balance
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\n" ); document.write( ".08x +8 = .12x +4.8
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\n" ); document.write( "3.2 = .04x
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\n" ); document.write( "80 = x,,,,,in ml
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\n" ); document.write( "check,,,,.08(80) +.2(40)= .12(120) = 14.4
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