document.write( "Question 1162778: A chemist has three different acid solutions. The first acid solution contains 15% acid, the second contains 30% and the third contains 70%. He wants to use all three solutions to obtain a mixture of 81 liters containing 55% acid, using 3 times as much of the 70% solution as the 30% solution. How many liters of each solution should be used? \n" ); document.write( "

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\n" ); document.write( "A chemist has three different acid solutions. The first acid solution contains 15% acid, the second contains 30% and the third contains 70%. He wants to use all three solutions to obtain a mixture of 81 liters containing 55% acid, using 3 times as much of the 70% solution as the 30% solution. How many liters of each solution should be used?
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Quite a few tutors have been PREACHING on here, the need to solve problems like these using ONE VARIABLE. I guess some who continue to use multiple 
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document.write( "variables - the likes of the other person who responded - don't feel that they need to learn the most efficient and least complex way to solutions.
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document.write( "Again, I would suggest that you don't solve this problem his way!\r
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document.write( "Let the amount of 30% solution, be T
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document.write( "Then amount of 70% solution is: 3T
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document.write( "Therefore, the amount of 15% solution is: 81 - (T + 3T), or 81 - 4T
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document.write( "We then get the following equation: .3T + .7(3T) + .15(81 - 4T) = .55(81)
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document.write( ".3T + 2.1T + .15(81) - .6T = .55(81)
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document.write( "1.8T = .55(81) - .15(81)
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document.write( "1.8T = .4(81)
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document.write( "Amount of 30% solution to mix, or 
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document.write( "Do you think you can now find the 70% and 15% amounts? \n" );
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