document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1123200>Question 1123200</A>: <I><SPAN STYLE=\"word-break: break-all;\">  A piece of metal is heated to 428 degree C before it is left to cool. The temperature of the metal falls at the rate of 23 degree C per minute for first three minutes, at the rate of 15 degree C per minute for the next 15 minutes and then at the rate of 8 degree C per minute until it reaches to room temperature of 25 degree C from 428 degree C <BR>\n" );
document.write( "i. Find Temperature of the metal after 9 minutes. <BR>\n" );
document.write( "ii. The total time needed for the metal to reach a temperature of 25 degree C from 428 degree C. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #739492 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=739492\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Temperature drops 23C*3 or 69C in 3 minutes<BR>\n" );
document.write( "15C per minute for the next 15 minutes, so that would be 90C in 6minutes for a total drop of 159C in 9 minutes. <BR>\n" );
document.write( "i.  428-159=269 C<BR>\n" );
document.write( "ii  3 minutes, drops 69 C, 15 minutes, drops 225 C, leaving 134 C as temp after 18 minutes. It is 109 C above 25 C, and it falls 8 C a minute or 109/8 = 13 5/8 minutes  more<BR>\n" );
document.write( "This requires 31 5/8 minutes or 31m37.5s </SPAN>\n" );
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