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 ? Choices
A) 2.10 p.m on wednesday.
B) 2.20 p.m on wednesday.
C) 2.30 p.m on wednesday.
D) 2.40 p.m on wednesday.
E) 2.00 p.m on wednesday.
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 \inline \left ( 2+4\frac{4}{5} \right ) min. or \inline \frac{34}{5} min. in 170 hrs.   Now, \inline \frac{34}{5} min. are gained in 170 hrs.   \inline \therefore 2 min are gained in \inline \left ( 170\times \frac{5}{34}\times 2 \right ) hrs = 50 hrs   \inline \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.   Answer 2.00 p.m on wednesday.
<result>E</result>
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 ?