min.48 Search

A watch which gains uniformly is 2 minutes low at noon on monday and is 4 min.48 sec fast at 2 p.m on the following monday. when was it correct ?

A) 2 p.m on Tuesday	B) 2 p.m on Wednesday
C) 3 p.m on Thursday	D) 1 p.m on Friday

Answer & Explanation Answer: B) 2 p.m on Wednesday

Explanation:

Time from 12 p.m on monday to 2 p.m on the following monday = 7 days 2 hours = 170 hours

Therefore, The watch gains $(2 + 4 \frac{4}{5})$ min. or 34/5 min. in 170 hrs.

Now, 34/5 min. are gained in 170 hrs.

Therefore, 2 min are gained in $(170 \times \frac{5}{34} \times 2)$ hrs = 50 hrs

Therefore, Watch is correct 2 days 2 hrs. after 12 p.m on monday i.e it will be correct at 2 p.m on wednesday.

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Filed Under: Clocks