Question

A watch which gains uniformly is 6 min slow at 5 p.m. on monday. on the following monday at 9 am, it was 10 min 40 seconds fast. when was it correct?

(a) 4:40 PM Monday

(b) 5:40 PM Monday

(c) 4:40 PM Tuesday

(d) 5:40 PM Tuesday

Answer 1

The watch was correct at 5:40 PM on Monday. The correct answer is (b) 5:40 PM Monday.

Step-by-step explanation:

To solve this problem, we need to find the time at which the watch was correct. We know that the watch gains uniformly and is 6 minutes slow at 5 p.m. on Monday and 10 minutes and 40 seconds fast at 9 a.m. on the following Monday. This means that the watch gains 16 minutes and 40 seconds in 16 hours (from 5 p.m. to 9 a.m.).

To find when the watch was correct, we can set up a proportion:

16 hours = 16 minutes and 40 seconds

x hours = 0 minutes

Cross multiplying, we get:

16 hours * 0 minutes = 16 minutes and 40 seconds * x hours

0 minutes = 16 minutes and 40 seconds * x hours

0 = 1000 seconds * x hours

x hours = 0

Therefore, the watch was correct at 5 p.m. on Monday, which is option (b) 5:40 PM Monday.