document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1155962>Question 1155962</A>: <I><SPAN STYLE=\"word-break: break-all;\"> With both the cold water and hot water faucets​ open, it takes 7 minutes to fill a bathtub. The cold water faucet alone takes 9 minutes to fill the tub. How long will it take to fill the tub with just the hot water​ faucet? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #778678 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=778678\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "All three solutions you have received so far use some variation of the same algebraic method.  Here is an alternative method that I find many students prefer.<br><BR>\n" );
document.write( "Consider the least common multiple (LCM) of the two given times, which is 63 minutes.<br><BR>\n" );
document.write( "With both faucets working, being able to fill the tub together in 7 minutes, in 63 minutes they could fill the tub 63/7 = 9 times.<br><BR>\n" );
document.write( "With only the cold water faucet working, being able to fill the tub alone in 9 minutes, in 63 minutes it could fill the tub 63/9 = 7 times.<br><BR>\n" );
document.write( "That means in 63 minutes the hot water faucet alone could fill the tub 9-7 = 2 times; that means the time it would take the hot water faucet alone to fill the tub (once) would be 63/2 = 31.5 minutes.<br><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );