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)\"\" \"About 
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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( "\"+%2820%2F%28x-4%29%29+-+%2820%2Fx%29+=+%281%2F4%29+\"\r
\n" ); document.write( "\n" ); document.write( "

\n" ); document.write( "Taking the LCM we get,\r
\n" ); document.write( "\n" ); document.write( "\"+%2820%28x%29+-+20%28x-4%29%29%2F%28x%28x-4%29%29+=+%281%2F4%29+\"\r
\n" ); document.write( "\n" ); document.write( "

\n" ); document.write( "\"+%2820x+-+20x+%2B+80%29%2F%28x%5E2+-+4x%29+=+%281%2F4%29+\"\r
\n" ); document.write( "\n" ); document.write( "
\r
\n" ); document.write( "\n" ); document.write( "\"+80%2F%28x%5E2+-+4x%29+=+%281%2F4%29+\"\r
\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( "\"+4%2880%29+=+%28x%5E2+-+4x%29+\"
\n" ); document.write( "\"+%28320%29+=+%28x%5E2+-+4x%29+\"\r
\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.
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