document.write( "Question 1030654: A long distance runner does a first lap around a track in
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Algebra.Com's Answer #645500 by Edwin McCravy(20054)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Her time for the first lap is 50 seconds\r\n" );
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document.write( "Her time for the second lap is \r\n" );
document.write( "50 seconds + 20% of 50 seconds =\r\n" );
document.write( "50 + 0.2×50 = 50 + 10 = 60 seconds.\r\n" );
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document.write( "Her time for the third lap is\r\n" );
document.write( "60 seconds + 20% of 60 seconds =\r\n" );
document.write( "60 + 0.2×60 = 60 + 12 = 72 seconds.\r\n" );
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document.write( "Total time = 50 sec + 60 sec + 72 sec =\r\n" );
document.write( "182 seconds = 3 minutes 2 seconds. \r\n" );
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document.write( "Easier and quicker way, but a tiny bit more advanced:\r\n" );
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document.write( "Think of \"20% longer\" as \"120% of\", so multiply by 1.2 each time\r\n" );
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document.write( "50+50×1.2+50×1.2×1.2 = 182 seconds = 3 minutes 2 seconds. \r\n" );
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document.write( "If you have a scientific calculator, you can put in \r\n" );
document.write( "50+50×1.2+50×1.2×1.2 in all at one time and press = or \"enter\".\r\n" );
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document.write( "Edwin
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