document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=731652>Question 731652</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how do we work out how to find the answers to all these question i have tried but i get different to the answers in the book and my son is in tears....\r<BR>\n" );
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document.write( "a/<BR>\n" );
document.write( "pumpa  can fill a tank in 5 mins while pump b can fill a tank in 10 mins. how long will it take to fill the tank if both are working together?\r<BR>\n" );
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document.write( "b/<BR>\n" );
document.write( "in making one revolution a car wheel travels 200cm . how fast are the wheels spinngin in revolutions per minute, when the car is travelling at 60km/h?\r<BR>\n" );
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document.write( "c/<BR>\n" );
document.write( "a girl paddles her kayak upstream from her home to her friends home takin 2.5 hours for the journedy. sher returns taht afternoon in 1.5 hrs .<BR>\n" );
document.write( "if the is flowing at 2.5 km/h find:<BR>\n" );
document.write( "1/ her paddling speed in still water<BR>\n" );
document.write( "2/ the distance to ther friends place. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #447218 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=447218\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> pump a can fill a tank in 5 mins while pump b can fill a tank in 10 mins<BR>\n" );
document.write( "how long will it take to fill the tank if both are working together?<BR>\n" );
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document.write( "let m = no. of minutes required when working together<BR>\n" );
document.write( "let the completed job = 1, (a full tank)<BR>\n" );
document.write( "each pump does a fraction of the job. The two fractions add up to 1<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m%2F5 ALIGN=MIDDLE  ALT=\"m%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m%2F10 ALIGN=MIDDLE  ALT=\"m%2F10\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "multiply by 10 to clear the denominators, resulting in:<BR>\n" );
document.write( "2m + m = 10<BR>\n" );
document.write( "3m = 10<BR>\n" );
document.write( "m = 10/3<BR>\n" );
document.write( "m = 3<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F3 ALIGN=MIDDLE  ALT=\"1%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > min working together<BR>\n" );
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document.write( "b/<BR>\n" );
document.write( "in making one revolution a car wheel travels 200cm.<BR>\n" );
document.write( " how fast are the wheels spinning in revolutions per minute,<BR>\n" );
document.write( " when the car is traveling at 60km/h?<BR>\n" );
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document.write( "Let r = number of revs at 60 km/hr (convert 60 km/h to cm/min<BR>\n" );
document.write( "r = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2860%2A1000%2A100%29%2F%28200%2A60%29 ALIGN=MIDDLE  ALT=\"%2860%2A1000%2A100%29%2F%28200%2A60%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "r = 500 rev per minute<BR>\n" );
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document.write( "c/<BR>\n" );
document.write( "a girl paddles her kayak upstream from her home to her friends home<BR>\n" );
document.write( " taking 2.5 hours for the journey. returns that afternoon in 1.5 hrs<BR>\n" );
document.write( "if the current is flowing at 2.5 km/h <BR>\n" );
document.write( "find:<BR>\n" );
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document.write( "1/ her paddling speed in still water<BR>\n" );
document.write( "let s = speed in still water<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s-2.5) = effective speed upstream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(s+2.5) = effective speed downstream<BR>\n" );
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document.write( "Write a distance equation; dist = time * speed<BR>\n" );
document.write( "Up dist = down dist<BR>\n" );
document.write( "2.5(s-2.5) = 1.5(s+2.5)<BR>\n" );
document.write( "2.5s - 6.25 = 1.5s + 3.75<BR>\n" );
document.write( "2.5s - 1.5s = 3.75 + 6.25<BR>\n" );
document.write( "1s = 10 km/hr in still water<BR>\n" );
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document.write( "2/ the distance to the friends place.<BR>\n" );
document.write( "Find the dist upstream<BR>\n" );
document.write( "2.5(10-2.5) =<BR>\n" );
document.write( "2.5(7.5) = 18.75 km<BR>\n" );
document.write( "check using downstream equation<BR>\n" );
document.write( "1.5(10+2.5) = 18.75 km also, confirms our solution<BR>\n" );
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document.write( "Hopefully, we can dry those tears! </SPAN>\n" );
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