document.write( "Question 614878: The rails of a railroad are 30 feet long. As a train passes over the point where the rails are joined, there is an audible click. The speed of the train in miles per hours is approximately the number of clicks head in how many seconds? \n" ); document.write( "

Algebra.Com's Answer #386800 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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The rails of a railroad are 30 feet long.
\n" ); document.write( " As a train passes over the point where the rails are joined, there is an audible click.
\n" ); document.write( "The speed of the train in miles per hours is approximately the number of clicks heard in how many seconds?
\n" ); document.write( ":
\n" ); document.write( "See how many clicks in 1 minute at 60 mph
\n" ); document.write( " $\"60%2A5280%2F%2830%2A60%29\"$ = 176 clicks in 1 minute
\n" ); document.write( ":
\n" ); document.write( "But they want to know how many seconds for 60 clicks to occur
\n" ); document.write( " $\"60%2F176\"$ = About 1/3 of a minute, 20 seconds
\n" ); document.write( ":
\n" ); document.write( "If you count 60 clicks in 20 seconds, the train is running 60 mph
\n" ); document.write( "If you count 40 clicks in 20 seconds, the train is running 40 mph
\n" ); document.write( ":
\n" ); document.write( "Let see if that is so.
\n" ); document.write( "40*30 = 1200 ft in 20 seconds, that 3600 ft in 1 minute
\n" ); document.write( " $\"%2860%2A3600%29%2F5280\"$ = 40.9 mph which is close enough
\n" ); document.write( ":
\n" ); document.write( "Summarize, \"count the clicks in 20 sec, this gives you the speed in mph\"
\n" ); document.write( " \n" ); document.write( "

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