document.write( "Question 360054: A clock is broken. But its hour hand, minute hand, and second hand still move
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Algebra.Com's Answer #256909 by Edwin McCravy(20056)\"\" \"About 
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A clock is broken. But its hour hand, minute hand, and second hand still move
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\n" ); document.write( "every 10 seconds (measured by an accurate clock) and passes the minute hand every 20 seconds. How often does the minute hand pass the hour hand?
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document.write( "Imagine yourself holding the clock in your hands and constantly turning the\r\n" );
document.write( "whole clock in the counterclockwise direction at the same speed the second hand\r\n" );
document.write( "is turning, so that the second hand doesn't move at all, but stays in the same\r\n" );
document.write( "place. \r\n" );
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document.write( "Now imagining that situation (with the second hand not moving at all), the hour\r\n" );
document.write( "hand makes one revolution every 10 seconds.  Therefore the hour hand's rate is\r\n" );
document.write( "360 degrees per 10 seconds or 36 degrees per second. \r\n" );
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document.write( "Still imagining that situation (with the second hand not moving at all), the\r\n" );
document.write( "minute hand makes one revolution every 20 seconds.  Therefore the minute hand's\r\n" );
document.write( "rate is 360 degrees per 20 seconds or 18 degrees per second. \r\n" );
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document.write( "So the angle between the hour and minute hands grows at the rate of 36-18 or 18\r\n" );
document.write( "degrees per second, and since 18 degrees per second is the same as 360 degrees\r\n" );
document.write( "per 20 seconds, then the angle between the hour and minute hands grows at the\r\n" );
document.write( "rate of 360 degrees per 20 seconds.  Therefore they pass each other every 20\r\n" );
document.write( "seconds.  \r\n" );
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document.write( "Edwin
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