document.write( "Question 636112: Two runners start running at the same time from start/finish line of a 400 meter oval track. One runner runs laps of 1 minute 15 seconds and the other runner runs laps of 1 minute 45 seconds. HOw long will it be before the runners cross the start/finish line at the smae time? How many laps will each have run? \n" ); document.write( "
Algebra.Com's Answer #400771 by ankor@dixie-net.com(22740)\"\" \"About 
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Two runners start running at the same time from start/finish line of a 400 meter oval track.
\n" ); document.write( " One runner runs laps of 1 minute 15 seconds and the other runner runs laps of 1 minute 45 seconds.
\n" ); document.write( " How long will it be before the runners cross the start/finish line at the same time?
\n" ); document.write( " How many laps will each have run?
\n" ); document.write( ":
\n" ); document.write( "Change 1 min 15 min to 75 sec; and 1 min 45 sec to 105 sec
\n" ); document.write( "Find least common multiple of 75 and 105 using prime factors
\n" ); document.write( "75: 3*5*5
\n" ); document.write( "105: 3*5*7
\n" ); document.write( "LCM: 3*5*5*7 = 525 sec
\n" ); document.write( "which is 525/60 = 8.75 min, which is:
\n" ); document.write( "8 min 45 sec when both runners cross the finish line at the same time
\n" ); document.write( "then
\n" ); document.write( "One runner completes exactly 525/75 = 7 laps
\n" ); document.write( "and
\n" ); document.write( "Other runner completes exactly 525/105 = 5 laps\r
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