document.write( "Question 1186342: At exactly 12 o’clock noon the hour hand of a clock begins to move at twice its
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Algebra.Com's Answer #840640 by ikleyn(52794) $\"\"$ $\"About$

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\n" ); document.write( "At exactly 12 o'clock noon the hour hand of a clock begins to move at twice its normal speed,
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\n" ); document.write( "When the two hands next coincide, what will be the correct time?
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document.write( "The normal angular speed of the hour hand is  360/12 = 30 degrees per hour;\r\n" );
document.write( "so, its doubled speed is 60 degree per hour.\r\n" );
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document.write( "The normal angular speed of the minute hand is  360 degrees per hour;\r\n" );
document.write( "so, half of its speed is 180 degrees per hour.\r\n" );
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document.write( "Thus, in this problem, the hour hand   rotates anti-clockwise at  60 degrees per hour; \r\n" );
document.write( "                       the minute hand rotates clockwise      at 180 degrees per hour.\r\n" );
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document.write( "They approach each other at the rate of (60+180) = 240 degrees per hour.\r\n" );
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document.write( "So, they coincide next time in  360/240 = 1 = 1.5 hours = 90 minutes.\r\n" );
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document.write( "When the clock hands coincide next time, the correct time is 1:30 pm.    ANSWER\r\n" );
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