2264:21:49.5
Soumyabrata Mondal how to solve it???Upvote·0· Reply ·2013-01-21 09:57:22
At what time after 4.00 p.m. is the minutes hand of a clock exactly aligned with the hour hand?
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2 Answers
226Assume that X minutes after 4.00 PM minute hand exactly
aligns with and hour hand.
For every minute, minute hand travels 6 degrees.
Hence, for X minutes it will travel 6 * X degrees.
For every minute, hour hand travels 1/2 degrees.
Hence, for X minutes it will travel X/2 degrees.
At 4.00 PM, the angle between minute hand and hour hand is
120 degrees. Also, after X minutes, minute hand and hour
hand are exactly aligned. So the angle with respect to 12
i.e. Vertical Plane will be same. Therefore,
6 * X = 120 + X/2
12 * X = 240 + X
11 * X = 240
X = 21.8182
X = 21 minutes 49.5 seconds
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