1.  A watch which gains uniformly is 2 minutes low at noon on Tuesday and is 4 min 48 sec fast at 2 p.m. on the following Tuesday. When was it correct ?
A. 12 p.m. on Wednesday
B. 2 p.m. on Thursday
C. 3 p.m. on Thursday
D. 2 p.m. on Wednesday

Answer: Option B

Explanation:

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

= 170 hours.

The watch gains = (2 + 4 x 4/5) min

= 34/5 min. in 170 hrs.

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

Then, 2 min are gained in (170 x 5/34 x 2) hrs.

Watch is correct after 2 days 2 hrs after 12 p.m. on Tuesday, i.e., it will be correct at 2 p.m. on Thursday.