document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=50474>Question 50474</A>: <I><SPAN STYLE=\"word-break: break-all;\"> <PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">My son is in 8th grade and I am trying to help him with\r\n" );
document.write( "math.  Please explain a formula to figure these types\r\n" );
document.write( "of problems.  Thanks\r\n" );
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document.write( "A bike costs $100 more than a scooter. A scooter costs $60\r\n" );
document.write( "more than a skateboard. the total cost of the 3 items is\r\n" );
document.write( "$310. How much is skateboard? Scooter? Bike?</PRE> </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #33525 by </B><A HREF=/tutors/aboutme.mpl?userid=tutorcecilia><B>tutorcecilia(2152)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tutorcecilia><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=tutorcecilia><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=33525\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Bike =  Scooter + $100<BR>\n" );
document.write( "Scooter = Skateboard + $60<BR>\n" );
document.write( "Skateboard = unknown cost = x<BR>\n" );
document.write( "Total cost of all three = $310<BR>\n" );
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document.write( "Bike + Scooter + Skateboard = $310 [Basic addition formula]<BR>\n" );
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document.write( "(Scooter + 100) + (Skateboard + 60) + (Skateboard) = 310 [Plug-in the values]<BR>\n" );
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document.write( "[(Skateboard + 60) + 100) + (Skateboard + 60) + (Skateboard)] = 310 <BR>\n" );
document.write( "[Substitute the value of the scooter for \"skateboard + 60\"]<BR>\n" );
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document.write( "((x + 60) + 100) + (x + 60) + (x) = 310 [Substitute \"x\" for \"skateboard\"]<BR>\n" );
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document.write( "x + 60 + 100 + x + 60 + x = 310 [Remove the parentheis and simplify (add)]<BR>\n" );
document.write( "3x + 220 = 310 [Here is the simplified equation of the problem]<BR>\n" );
document.write( "3x + 220 - 220 = 310 - 220 [solve for x]<BR>\n" );
document.write( "3x= 90<BR>\n" );
document.write( "3x/3=90/3<BR>\n" );
document.write( "x=30<BR>\n" );
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document.write( "Plug-in the values of the scooter to find the value of the other items:<BR>\n" );
document.write( "Bike =  Scooter + $100<BR>\n" );
document.write( "Scooter = $30 + $60 = $90<BR>\n" );
document.write( "Skateboard = x = $30 <BR>\n" );
document.write( "Total cost of all three = $310<BR>\n" );
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document.write( "Bike =  $90 + $100 = $190<BR>\n" );
document.write( "Scooter = $30 + $60 = $90<BR>\n" );
document.write( "Skateboard = x = $30 <BR>\n" );
document.write( "Total cost of all three = $310<BR>\n" );
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document.write( "Check by plugging in all of the values back into the basic formula of addition<BR>\n" );
document.write( "190+90+30=310<BR>\n" );
document.write( "310=310 [Checks out]\r<BR>\n" );
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