document.write( "Question 183621: I am currently taking Algebra 1, and need assistance with the following word problems (that use substitution, of course):\r
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document.write( "1.)Lisa and Beverly had just $5 to spend for an after-school snack. They could have bought 2 hamburgers and 1 carton of milk with no change back or 1 hamburger and 2 cartons of milk with 40 cents change back. How much does a carton of milk cost?\r
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document.write( "2.)If you buy six pens and one mechanical pencil, you'll get only $1 change from your $10 bill. But if you buy four pens and two mechanical pencils, you'll get $2 change. How much does each pen and each pencil cost?\r
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document.write( "3.)One number is 16 more than another. If the smaller number is subtracted from two-thirds of the larger number, the result is one-fourth of the sum of the two numbers. Find the numbers.\r
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document.write( "Thank you very much! An answer as immediate as possible would be greatly appreciated. \n" );
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Algebra.Com's Answer #137836 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! 1.)Lisa and Beverly had just $5 to spend for an after-school snack. They could have bought 2 hamburgers and 1 carton of milk with no change back or 1 hamburger and 2 cartons of milk with 40 cents change back. How much does a carton of milk cost \n" ); document.write( "--------- \n" ); document.write( "2h + c = 500 cents \n" ); document.write( "h + 2c= 460 cents \n" ); document.write( "--------------------- \n" ); document.write( "Prepare for substitution: \n" ); document.write( "c = 500 -2h \n" ); document.write( "----------------------- \n" ); document.write( "Substitute to solve for \"h\": \n" ); document.write( "h + 2(500-2h) = 460 \n" ); document.write( "h 1000 -4h = 460 \n" ); document.write( "-3h = -540 \n" ); document.write( "h = 180 cents = $1.80 (the price of a hamburger) \n" ); document.write( "----------------- \n" ); document.write( "Substitute to solve for \"c\": \n" ); document.write( "c = 500 - 2(180) \n" ); document.write( "c = 500 - 360 \n" ); document.write( "c = 140 cents = $1.40 (the price of a carton of mild) \n" ); document.write( "--------------------------------------------------------------\r \n" ); document.write( "\n" ); document.write( "2.)If you buy six pens and one mechanical pencil, you'll get only $1 change from your $10 bill. But if you buy four pens and two mechanical pencils, you'll get $2 change. How much does each pen and each pencil cost? \n" ); document.write( "--- \n" ); document.write( "Equations: \n" ); document.write( "6p + m = 900 cents \n" ); document.write( "4p +2m = 800 cents \n" ); document.write( "------------------ \n" ); document.write( "Prepare for substitution: \n" ); document.write( "m = 900-6p \n" ); document.write( "-------------- \n" ); document.write( "Substitute to solve for \"p\": \n" ); document.write( "4p + 2(900-6p) = 800 \n" ); document.write( "4p + 1800 - 12p = 800 \n" ); document.write( "-8p = -1000 \n" ); document.write( "p = 125 cents = $1.25 (price of a pen) \n" ); document.write( "---------- \n" ); document.write( "Substitute to solve for mechanical pencil: \n" ); document.write( "m = 900 - 6p \n" ); document.write( "m = 900 - 6(125) \n" ); document.write( "m = 900 - 750 = 150 cents = $1.50 (price of a mechanical pencil) \n" ); document.write( "---------------------------------------------------- \n" ); document.write( " \n" ); document.write( "3.)One number is 16 more than another. If the smaller number is subtracted from two-thirds of the larger number, the result is one-fourth of the sum of the two numbers. Find the numbers. \n" ); document.write( "--- \n" ); document.write( "Equations: \n" ); document.write( "x = y - 16 \n" ); document.write( "(2/3)y - x = (1/4)(x+y) \n" ); document.write( "--------------- \n" ); document.write( "Simplify the 2nd equation: \n" ); document.write( "8y - 12x = 3x + 3y \n" ); document.write( "15x = 5y \n" ); document.write( "x = (1/3)y \n" ); document.write( "------------------- \n" ); document.write( "Substitute to solve for \"Y\": \n" ); document.write( "(1/3)y = y - 16 \n" ); document.write( "(2/3)y = 16 \n" ); document.write( "(1/3)y = 8 \n" ); document.write( "y = 24 \n" ); document.write( "------------- \n" ); document.write( "Substitute to solve for \"x\": \n" ); document.write( "x = (1/3)y = 8 \n" ); document.write( "============================= \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " \n" ); document.write( " |