document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1201379>Question 1201379</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Patty takes two hours to ice a cake alone, whereas Bob takes three hours to ice a cake alone. The number of hours it would take Patty and Bob working together to ice a cake is\r<BR>\n" );
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document.write( "a) 1 1/5 b) 1 1/4 c) 1 1/3 d) 2 1/2 e) 5 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #835712 by </B><A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><B>math_tutor2020(3817)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=835712\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "Let's say the cake's surface area is 60 square inches.<BR>\n" );
document.write( "I picked a value that is a common multiple between 2 and 3 (since 2*3 = 6).<BR>\n" );
document.write( "It turns out that the surface area doesn't matter since we'll get the same answer for other surface area values.<BR>\n" );
document.write( "Feel free to pick some other positive number.\r<BR>\n" );
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document.write( "Patty takes 2 hours to cover 60 square inches when working alone.<BR>\n" );
document.write( "Her rate is 60/2 = 30 sq in per hour.<BR>\n" );
document.write( "The formula I used is: <BR>\n" );
document.write( "rate = (amount done)/(time)\r<BR>\n" );
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document.write( "Bob takes 3 hours to cover 60 square inches when working alone.<BR>\n" );
document.write( "His rate is 60/3 = 20 sq in per hour.\r<BR>\n" );
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document.write( "Their combined rate is 30+20 = 50 sq in per hour.\r<BR>\n" );
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document.write( "If the two team up, and don't get in each other's way, then their combined rate is 50 sq in per hour.\r<BR>\n" );
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document.write( "Let's determine how long they take when working together.<BR>\n" );
document.write( "rate = (amount done)/(time)<BR>\n" );
document.write( "rate*time = amount done<BR>\n" );
document.write( "time = (amount done)/(rate)<BR>\n" );
document.write( "time = (60 sq in)/(50 sq in per hr)<BR>\n" );
document.write( "time = (60/50) hr<BR>\n" );
document.write( "time = (6/5) hr<BR>\n" );
document.write( "time = ( (5+1)/5 ) hr<BR>\n" );
document.write( "time = ( 5/5 + 1/5 ) hr<BR>\n" );
document.write( "time = <font color=red>( 1 + 1/5 ) hr</font>\r<BR>\n" );
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document.write( "Side notes:<BR>\n" );
document.write( "1 hr + 1/5 hr = 1 hr + 0.2 hr = 1.2 hr<BR>\n" );
document.write( "or <BR>\n" );
document.write( "1 hr + 1/5 hr = 60 min + (1/5)*(60) min = 60 min + 12 min = 72 min<BR>\n" );
document.write( "or<BR>\n" );
document.write( "1 hr + 1/5 hr = 1 hr + 12 min\r<BR>\n" );
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document.write( "Answer: <font color=red size=4> Choice A) 1  1/5 </font><BR>\n" );
document.write( "This is the mixed number 1 & 1/5<BR>\n" );
document.write( "whole part = 1<BR>\n" );
document.write( "fractional part = 1/5<BR>\n" );
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