document.write( "Question 207220: I need assistance with two separate word problems.\r
\n" ); document.write( "\n" ); document.write( "1) A car radiator contains 10 liters of a 30% solution. How many liters will have to be replaced with pure antifreeze if the resulting solution is to be 50% antifreeze?\r
\n" ); document.write( "\n" ); document.write( "2) You are planning to start a business that will require an investment of $90,000. You have found some people who are willing to share equally in the venture. If you find three more people, each person's share will decrease by $2500. how many people have you found so far?\r
\n" ); document.write( "\n" ); document.write( "Thank you immensely, \r
\n" ); document.write( "\n" ); document.write( "Andrew
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Algebra.Com's Answer #156755 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
1) A car radiator contains 10 liters of a 30% solution.
\n" ); document.write( " How many liters will have to be replaced with pure antifreeze if the resulting
\n" ); document.write( " solution is to be 50% antifreeze?
\n" ); document.write( ":
\n" ); document.write( "let x = amt of pure antifreeze to be added
\n" ); document.write( "and also
\n" ); document.write( "let x = amt of 30% solution to be removed
\n" ); document.write( ":
\n" ); document.write( ".30(10-x) + x = .50(10)
\n" ); document.write( ":
\n" ); document.write( "3 - .3x + x = 5
\n" ); document.write( ":
\n" ); document.write( "-.3x + 1x = 5 - 3
\n" ); document.write( ":
\n" ); document.write( ".7x = 2
\n" ); document.write( "x = \"2%2F.7\"
\n" ); document.write( "x = 2.857 liters of 30% solution replaced by pure antifreeze
\n" ); document.write( ":
\n" ); document.write( "Check solution:
\n" ); document.write( ".30(10-2.857) + 2.857 = .50(10)
\n" ); document.write( "2.143 + 2.857 = 5
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "2) You are planning to start a business that will require an investment of $90,000.
\n" ); document.write( "You have found some people who are willing to share equally in the venture.
\n" ); document.write( " If you find three more people, each person's share will decrease by $2500.
\n" ); document.write( " how many people have you found so far?
\n" ); document.write( ":
\n" ); document.write( "Let x = no. of people so far:
\n" ); document.write( "then
\n" ); document.write( "(x+3) = no. of people to decrease share by $2500
\n" ); document.write( ":
\n" ); document.write( "Original share amt = Three more share amt + $2500
\n" ); document.write( "\"90000%2Fx\" = \"90000%2F%28%28x%2B3%29%29\" + 2500
\n" ); document.write( "Multiply equation x(x+3); results
\n" ); document.write( "90000(x+3) = 90000x + 2500x(x+3)
\n" ); document.write( ":
\n" ); document.write( "90000x + 270000 = 90000x + 2500x^2 + 7500x
\n" ); document.write( ":
\n" ); document.write( "Arrange on the right:
\n" ); document.write( "0 = 90000x - 90000x + 2500x^2 + 7500x - 270000
\n" ); document.write( ":
\n" ); document.write( "A quadratic equation:
\n" ); document.write( "2500x^2 + 7500x - 270000 = 0
\n" ); document.write( ":
\n" ); document.write( "Simplify, divide by 2500
\n" ); document.write( "x^2 + 3x - 108 = 0
\n" ); document.write( ":
\n" ); document.write( "Factors to:
\n" ); document.write( "(x+12)(x-9) = 0
\n" ); document.write( "Positive solution
\n" ); document.write( "x = 9 people originally
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check solution:
\n" ); document.write( "90000/9 = 10000
\n" ); document.write( "90000/12 = 7500
\n" ); document.write( "----------------
\n" ); document.write( "difference 2500
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