document.write( "Question 767060: It is desired to draw off a part of 10 gallons of 30% solution of alcohol and to replace it by pure alcohol so as to produce a 50% solution. How many gallons should be drawn off? \n" ); document.write( "

Algebra.Com's Answer #467407 by ramkikk66(644) $\"\"$ $\"About$

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document.write( "It is desired to draw off a part of 10 gallons of 30% solution of alcohol and to replace it by pure alcohol so as to produce a 50% solution. How many gallons should be drawn off?\r
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document.write( "Let us assume x gallons is drawn off and replaced with x gal of pure alcohol.\r
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document.write( "After drawing of x gallons of the 30% mix, what is left is (10 - x) gallons of 
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document.write( "30% mix.\r
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document.write( "Since it is a 30% mix, volume of alcohol in it = (10 - x)*30% = (10 - x)*0.3
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document.write( "= 3 - 0.3*x\r
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document.write( "After adding x gallons of pure alcohol, the total volume of the mix is again
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document.write( "back to 10 gallons.\r
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document.write( "In this new mix, the volume of alcohol is = original alcohol + x gallons =
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document.write( "(3 - 0.3*x) + x = 3 + 0.7*x\r
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document.write( "Now, this is given to be a 50% mix. i.e. ratio of alcohol in the mix is 0.5\r
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document.write( "Therefore, \r
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document.write( " gallons\r
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document.write( "Hope you got it :)\r
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