document.write( "Question 410882: Suppose you bought supplies for a party. Three rolls of streamers and 15 balloons cost $30. Later, you bought 2 rolls of streamers and 4 baloons for $11. How much did each roll of streamers cost? How much did each balloon cost? (could you also explain how you got the answer?) \n" ); document.write( "
Algebra.Com's Answer #288854 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! Three rolls of streamers and 15 balloons cost $30. Later, you bought 2 rolls of streamers and 4 baloons for $11. How much did each roll of streamers cost? \n" ); document.write( "----- \n" ); document.write( "Equations: \n" ); document.write( "3s + 15b = 30 dollars \n" ); document.write( "2s + 4b = 11 dollars \n" ); document.write( "-------------- \n" ); document.write( "Multiply thru 1st by 4 \n" ); document.write( "Multiply thru the 2nd by 15 \n" ); document.write( "------- \n" ); document.write( "12s + 60b = 120 \n" ); document.write( "30s + 60b = 165 \n" ); document.write( "---- \n" ); document.write( "Subtract and solve for \"s\": \n" ); document.write( "18s = 45 \n" ); document.write( "s = 5/2 dollars \n" ); document.write( "streamers cost $2.50 \n" ); document.write( "========================== \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( "============== \n" ); document.write( " |