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What is the angle between the hour-hand and minute-hand of a clock at 3:15?

At quarter past the hour, the minute-hand is exactly at 3:00 but the hour-hand has moved 1/4 of the way between 3:00 and 4:00.  Therefore 1/4 times 1/12 = 1/48 of the clock.  With the clock having 360 degrees, 360/48 = 7.5 degrees.

November 5th, 2007 | Category: Interviewing - Brainteasers

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