document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1184603>Question 1184603</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Biologists have found that the number of chirps some crickets make per minute is related to temperature. When crickets chirp 124 times a minute, it is about 68 degrees Fahrenheit. When they chirp 172 times a minute, it is about 80 degrees Fahrenheit. How warm is it when the crickets are chirping 150 times a minute? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #815255 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=815255\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "A formal algebraic solution like the one provided by the other tutor is probably what was expected from the student.<br><BR>\n" );
document.write( "But the same calculations can be done informally to reach the answer faster and with less work.<br><BR>\n" );
document.write( "The two given temperatures are 68 and 80 degrees, a difference of 12 degrees.<BR>\n" );
document.write( "The two rates of chirping are 124 and 172, a difference of 48.<br><BR>\n" );
document.write( "Assuming a linear relationship (which should be stated in the problem, but which we have to assume in order to solve the problem), the rate of chirping increases by 48/12=4 for each increase of 1 degree of temperature.<br><BR>\n" );
document.write( "150 chirps per minute is 26 more than the 124 per minute at 68 degrees.  Since the rate of increase is 4 chirps for each degree increase of temperature, the increase in temperature from 68 degrees to get 150 chirps per minute is 26/4=6.5 degrees.  So<br><BR>\n" );
document.write( "ANSWER: The temperature at which the crickets will chirp at a rate of 150 per minute is 68+6.5=74.5 degrees.<br><BR>\n" );
document.write( "All the words of explanation make this sound like a long and complicated problem.  But the calculations alone are few and easy:<br><BR>\n" );
document.write( "80-68=12<BR>\n" );
document.write( "172-124=48<BR>\n" );
document.write( "48/12=4<BR>\n" );
document.write( "150-124=26<BR>\n" );
document.write( "26/4=6.5<BR>\n" );
document.write( "68+6.5=74.5<br><BR>\n" );
document.write( " </SPAN>\n" );
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