document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1149233>Question 1149233</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Two planes, which are 2160 miles apart, fly toward each other.  Their speeds differ by 40mph.  If they pass each other in 4 hours, what is the speed of each?<BR>\n" );
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document.write( "Using algebra....<br><BR>\n" );
document.write( "Let the speeds be x and x+40.  Then<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%28x%29%2B4%28x%2B40%29+=+2160 ALIGN=MIDDLE  ALT=\"4%28x%29%2B4%28x%2B40%29+=+2160\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "Solve using basic algebra....<br><BR>\n" );
document.write( "Using logical analysis and simple mental arithmetic....<br><BR>\n" );
document.write( "The combined speed is 2160/4 = 540.<BR>\n" );
document.write( "If the two speeds were the same, they would each be 270; 270+270=540.<BR>\n" );
document.write( "To get two speeds that differ by 40mph, add 20mph to one speed and subtract 20mph from the other.<br><BR>\n" );
document.write( "ANSWER: 270+20 = 290mph and 270-20 = 250mph<br><BR>\n" );
document.write( "CHECK:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%28290%29%2B4%28250%29+=+1160%2B1000+=+2160 ALIGN=MIDDLE  ALT=\"4%28290%29%2B4%28250%29+=+1160%2B1000+=+2160\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
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