document.write( "Question 230553: Carlos has some pennies, nickels, and quarters in his pocket. He has 2 more nickels than quarters. He has twice as many pennies as nickels. The total value is $1.74. How many of each coin does Carlos have? \n" ); document.write( "
Algebra.Com's Answer #170713 by likaaka(51)![]() ![]() ![]() You can put this solution on YOUR website! First begin by naming your variables. \n" ); document.write( "Let P be the amount, not worth, of pennies Carlos has, N will be the amount of nickels, and Q the amount of quarters. \n" ); document.write( "So if Carlos has 2 more nickels than quarters, your first equation is \n" ); document.write( "N = Q + 2 \n" ); document.write( "If he has twice as many pennies as nickels, then \n" ); document.write( "P = 2N \n" ); document.write( "Now we use the value of each coin to determine the third equation. \n" ); document.write( "0.01P + 0.05N + 0.25Q = 1.74\r \n" ); document.write( "\n" ); document.write( "Here's your system of equations \n" ); document.write( "N = Q + 2 \n" ); document.write( "P = 2N \n" ); document.write( "0.01P + 0.05N + 0.25Q = 1.74 \n" ); document.write( "I would start be rearranging the first equation so that it's solved for Q \n" ); document.write( "N = Q + 2 becomes Q = N - 2 by subtracting 2 from both sides\r \n" ); document.write( "\n" ); document.write( "Now substitute the value of Q and the value of P into the third equation to solve for N \n" ); document.write( "0.01(2N) + 0.05N + 0.25(N-2) = 1.74, distribute \n" ); document.write( "0.02N + 0.05N + 0.25N - 0.5 = 1.74, combine like terms \n" ); document.write( "0.32N - 0.5 = 1.74, add 0.5 to both sides \n" ); document.write( "0.32N = 2.24, divide both sides by 0.32 \n" ); document.write( "N = 7, so Carlos has 7 nickels\r \n" ); document.write( "\n" ); document.write( "Given Q = N - 2 and N = 7 solve for Q \n" ); document.write( "Q = 7 - 2 \n" ); document.write( "Q = 5, so Carlos has 5 quarters\r \n" ); document.write( "\n" ); document.write( "Given P = 2N and N = 7 \n" ); document.write( "P = 2(7) \n" ); document.write( "P = 14, so Carlos has 14 pennies\r \n" ); document.write( "\n" ); document.write( "CHECK: \n" ); document.write( "0.01(14) + 0.05(7) + 0.25(5) = 1.74 \n" ); document.write( "0.14 + 0.35 + 1.25 = 1.74 \n" ); document.write( "1.74 = 1.74 \n" ); document.write( " \n" ); document.write( " |