document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=48949>Question 48949</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A reservoir has two drain systems, large & small.  Six large drains, on their own, can drain the reservoir in 12 hours.  Three large pipes and 9 small pipes can drain it in 8 hours.  How long will it take 5 small pipes to drain the reservoir. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #32413 by </B><A HREF=/tutors/aboutme.mpl?userid=venugopalramana><B>venugopalramana(3286)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=venugopalramana><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.geocities.com/venugopalramana/FREE_MATHS_ASSISTANCE.html valign=middle><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=32413\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  more important is your statement that it is for 6 th.grade<BR>\n" );
document.write( "test and your mention on algebra.if it is for 6 th. grade ,they may<BR>\n" );
document.write( "not be exposed to algebra that much and hence my answer is of no use<BR>\n" );
document.write( ",if it is not ubderstood by the student.so let me give you below a<BR>\n" );
document.write( "method  which needs only general maths principles.<BR>\n" );
document.write( "Question 48949: A reservoir has two drain systems, large & small. Six<BR>\n" );
document.write( "large drains, on their own, can drain the reservoir in 12 hours. Three<BR>\n" );
document.write( "large pipes and 9 small pipes can drain it in 8 hours. How long will<BR>\n" );
document.write( "it take 5 small pipes to drain the reservoir.<BR>\n" );
document.write( ": A reservoir has two drain systems, large & small. Six large drains,<BR>\n" );
document.write( "on their own, can drain the reservoir in 12 hours. Three large pipes<BR>\n" );
document.write( "and 9 small pipes can drain it in 8 hours. How long will it take 5<BR>\n" );
document.write( "small pipes to drain the reservoir.<BR>\n" );
document.write( "6..................... large drains....... can drain  in ...........12<BR>\n" );
document.write( "hours.....................1 reservoir<BR>\n" );
document.write( "6........................<BR>\n" );
document.write( "l.d.....................................................1.h..............................1/12<BR>\n" );
document.write( "r<BR>\n" );
document.write( "1.........................l.d.....................................................1.h.................1/(12*6)=1/72<BR>\n" );
document.write( "r<BR>\n" );
document.write( "-----------------------------------------------------------------------------------------------------------------<BR>\n" );
document.write( "3 l + 9 s........................................................................8<BR>\n" );
document.write( "h.........................1 r<BR>\n" );
document.write( "3 l + 9 s.........................................................................1............................1/8<BR>\n" );
document.write( "r<BR>\n" );
document.write( "but from above 1 large can drain in 1 hr 1/72 r...hence 3 l can drain<BR>\n" );
document.write( "in 1 hr..3/72=1/24 r<BR>\n" );
document.write( "hence 9 s can drain in 1 hr ....1/8 - 1/24 =2/24=1/12 r.<BR>\n" );
document.write( "9 s..................................................................................1............................1/12<BR>\n" );
document.write( "r<BR>\n" );
document.write( "1 s..................................................................................1.............................1/108<BR>\n" );
document.write( "r<BR>\n" );
document.write( "----------------------------------------------------------------------------------------------------------------------<BR>\n" );
document.write( "from above  5 s will drain<BR>\n" );
document.write( " 5s................................................................................1....................5*1/108=5/108<BR>\n" );
document.write( "r<BR>\n" );
document.write( "5 s will need .................................................................108/5<BR>\n" );
document.write( "hrs.............1 r<BR>\n" );
document.write( "answer =21.6 hrs.<BR>\n" );
document.write( "hope this will be clear to your child.\r<BR>\n" );
document.write( "\n" );
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document.write( "A reservoir has two drain systems, large & small. Six large drains, on their own, can drain the reservoir in 12 hours. Three large pipes and 9 small pipes can drain it in 8 hours. How long will it take 5 small pipes to drain the reservoir.<BR>\n" );
document.write( "LET EACH LARGE DRAIN CAPACITY =L<BR>\n" );
document.write( "LET EACH SMALL DRAIN CAPACITY=S<BR>\n" );
document.write( "SIX LARGE HAS=6L CAP.<BR>\n" );
document.write( "LET RESERVOIR VOLUME =R<BR>\n" );
document.write( "TIME TAKEN TO DRAIN WITH 6 LARGE=R/6L=12 HRS................<BR>\n" );
document.write( "L=R/72..................I<BR>\n" );
document.write( "3 LARGE HAS =3L CAP.<BR>\n" );
document.write( "9 SMALL HAS =9S CAP.<BR>\n" );
document.write( "TOTAL DRAIN CAP.=3L+9S=3(L+3S)<BR>\n" );
document.write( "TIME TAKEN TO DRAIN=R/3(L+3S)=8......................<BR>\n" );
document.write( "L+3S=R/24<BR>\n" );
document.write( "3S=(R/24)-(R/72)=2R/72=R/36<BR>\n" );
document.write( "S=R/108<BR>\n" );
document.write( "5 SMALL CAP.=5S=5R/108<BR>\n" );
document.write( "HENCE TIME NEEDED TO DRAIN =R/(5R/108)=108/5=21.6 HRS </SPAN>\n" );
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