document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=876268>Question 876268</A>: <I><SPAN STYLE=\"word-break: break-all;\"> We are told by geographers that the length of a river is approximately proportional to the 0.6th power of the basin of land that it drains. Expressed as a formula, this is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L=k%2AA%5E%280.6%29 ALIGN=MIDDLE  ALT=\"L=k%2AA%5E%280.6%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, where L is the length of the river in kilometres and k is a non-zero constant.\r<BR>\n" );
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document.write( "a) The Rio Grande drains a basin about <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=500+000km%5E2 ALIGN=MIDDLE  ALT=\"500+000km%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and is 3034 km long. Find k to three decimal places and write L as a function of A.\r<BR>\n" );
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document.write( "b)Find to the nearest kilometre, the length of a river that drains a basin of about <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20+000km%5E2 ALIGN=MIDDLE  ALT=\"20+000km%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #528669 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=528669\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> L = k * A^0.6<BR>\n" );
document.write( "a) L = 3034 and A = 500000<BR>\n" );
document.write( "k = 3034 / (500000^0.6)<BR>\n" );
document.write( "k = 1.155<BR>\n" );
document.write( "L = 1.155 * A^0.6<BR>\n" );
document.write( "b) L = 1.155 * 20000^0.6<BR>\n" );
document.write( "L = 439.744<BR>\n" );
document.write( "L = 440 kilometres\r<BR>\n" );
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