document.write( "Question 776945: A collection of 40 dimes and quarters has a value of $6.40. How many of each coin type are in the collection? \n" ); document.write( "
Algebra.Com's Answer #473824 by FrankM(1040) You can put this solution on YOUR website! 10D + 25Q = 640 (you see that a dime is 10 cents, and quarter, 25 cents) \n" ); document.write( "D + Q = 40 (there are 40 coins) \r \n" ); document.write( "\n" ); document.write( "Multiply both sides of second equation by -10 to get\r \n" ); document.write( "\n" ); document.write( "-10D - 10Q = -400 and add to first equation \r \n" ); document.write( "\n" ); document.write( "0D + 15Q = 240\r \n" ); document.write( "\n" ); document.write( "Q = 16 \n" ); document.write( "D = 40-16 = 24\r \n" ); document.write( "\n" ); document.write( "16 quarters are $4.00 \n" ); document.write( "24 dimes are $2.40\r \n" ); document.write( "\n" ); document.write( "$6.40 total \n" ); document.write( " |