document.write( "Question 640123: if i had one dollar and i brought 100 pieces of candy, some at 5 cent each and some at 2 cent each and some at 10 for 1 cents , so how many pieces of candy did i purchase at each cent.
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Algebra.Com's Answer #403074 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! If I had one dollar and I brought 100 pieces of candy; \n" ); document.write( " some at 5 cent each, and some at 2 cent each, and some at 10 for 1 cents, \n" ); document.write( " How many pieces of candy did I purchase at each cent. \n" ); document.write( ": \n" ); document.write( "Let x = no. of 5 cent candies \n" ); document.write( "Let y = no. of 2 cent candies \n" ); document.write( "Let z = no. of 10 for 1 cent \n" ); document.write( ": \n" ); document.write( "x + y + z = 100 candies \n" ); document.write( ": \n" ); document.write( "5x + 2y + .1z = 100 cents \n" ); document.write( "We have 3 unknowns and two equations, but we know 10 for one cent, \n" ); document.write( "candies has to be a multiple of 10, and <100 \n" ); document.write( ": \n" ); document.write( "Let z = 70 candies \n" ); document.write( "x + y + 70 = 100 \n" ); document.write( "x + y = 30; subtracted 70 from both sides \n" ); document.write( "then \n" ); document.write( "5x + 2y + .1(70) = 100 \n" ); document.write( "5x + 2y + 7 = 100 \n" ); document.write( "5x + 2y = 93; subtracted 7 from both sides \n" ); document.write( ": \n" ); document.write( "Multiply the 1st equation by 2, subtract from the above equation \n" ); document.write( "5x + 2y = 93 \n" ); document.write( "2x + 2y = 60 \n" ); document.write( "-------------- subtraction eliminates y, find x \n" ); document.write( "3x = 33 \n" ); document.write( "x = 11 ea 5 cent candies \n" ); document.write( ": \n" ); document.write( "Find y \n" ); document.write( "x + y + z = 100 \n" ); document.write( "11 + y + 70 = 100 \n" ); document.write( "y = 100 - 81 \n" ); document.write( "y = 19 ea 2 cent candies \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "See if that works \n" ); document.write( "5(11) + 2(19) + .1(70) = \n" ); document.write( "55 + 38 + 7 = 100 cents \n" ); document.write( ": \n" ); document.write( "Summarize \n" ); document.write( "11 ea 5 cent candies \n" ); document.write( "19 ea 2 cent candies \n" ); document.write( "70 ea 10/1 cent candies \n" ); document.write( " \n" ); document.write( " |