document.write( "Question 2792: Students sent flowers costing $20 to a sick classmate. There were 4 fewer students contributing than was planned, requiring of the others to pay 25 cents more than their original share. How many students contributed to buying the flowers? \n" ); document.write( "
Algebra.Com's Answer #1231 by xcentaur(357)![]() ![]() ![]() You can put this solution on YOUR website! Let the total number of students supposed to be contributing be 'x'.\r \n" ); document.write( "\n" ); document.write( "Let cost of each student be M = 20/x.\r \n" ); document.write( "\n" ); document.write( "Now,actual number of students contributing = (x-4).\r \n" ); document.write( "\n" ); document.write( "Let actual cost of each student be N = 20/(x-4).\r \n" ); document.write( "\n" ); document.write( "When there were 4 students less,they paid 25 cents more.\r \n" ); document.write( "\n" ); document.write( "This means that N > M by 25 cents.\r \n" ); document.write( "\n" ); document.write( "Therefore,\r \n" ); document.write( "\n" ); document.write( " N-M=25 Cents or $(1/4)\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "Then we get,\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "Taking the LCM we get,\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r \n" ); document.write( "\n" ); document.write( "On cross multiplying we get,\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r \n" ); document.write( "\n" ); document.write( "Taking 320 to the other side we get,\r \n" ); document.write( "\n" ); document.write( "x^2 - 4x - 320 = 0\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "Factorizing 320 to get a difference of 4 we get,\r \n" ); document.write( "\n" ); document.write( "x^2 - 16x + 20x - 320 = 0 \n" ); document.write( " \n" ); document.write( "x(x-16) + 20(x-16) = 0 \n" ); document.write( " \n" ); document.write( "(x-16)(x+20) = 0 \n" ); document.write( " \n" ); document.write( "Then we get, \n" ); document.write( "x=16 OR x=-20 \n" ); document.write( " \n" ); document.write( "As number of students cannot be negative, \n" ); document.write( "x=16 is the required value of x. \n" ); document.write( " \n" ); document.write( "Then number of students contributing is (x-4) = 12 students.\r \n" ); document.write( "\n" ); document.write( "ANS: 12 students contributed.\r \n" ); document.write( "\n" ); document.write( "Hope this helped, \n" ); document.write( "Best of luck. \n" ); document.write( " |