Question

A watch which gains uniformly is 2 minutes slow at 10:00 AM on Monday and is $2\frac{1}{2}$ minutes fast at 1:00 PM the following day. When did it show the correct time ?

Accepted Answer

D. Time interval from 10:00 AM Monday to 1:00 PM Tuesday = 27 hours. Total gain = $2 + 2.5 = 4.5$ minutes. Time required to gain 2 minutes (to correct the initial 2 min delay): $	ext{Hours} = \frac{27}{4.5} 	imes 2 = 6 	imes 2 = 12$ hours. 12 hours after 10:00 AM Monday is 10:00 PM Monday. Hence, Option D is correct.

Gaining Clock Correct Time

Explanation

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