Aptitude - Clock - Discussion
Discussion Forum : Clock - General Questions (Q.No. 19)
19.
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?
Answer: Option
Explanation:
Time from 12 p.m. on Monday to 2 p.m. on the following Monday = 7 days 2 hours = 170 hours.
 The watch gains |
 |
2 + 4 | 4 |  min. |
or | 34 | min. in 170 hrs. |
| 5 | 5 |
| Now, | 34 | min. are gained in 170 hrs. |
| 5 |
| 2 min. are gained in |
|
170 x | 5 | x 2 | hrs |
= 50 hrs. |
| 34 |
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.
Discussion:
56 comments Page 6 of 6.
Pratik said:
9 years ago
Great explanation @Madhu.
Beatrice Abongo` said:
9 years ago
What will be the answer for the question?
A watch loses 5 seconds every 2 hours it is set on Wednesday at 10:00 am what time will it show the following Wednesday at 10:00 am?
A watch loses 5 seconds every 2 hours it is set on Wednesday at 10:00 am what time will it show the following Wednesday at 10:00 am?
Akash Vashista said:
9 years ago
Here, the clock was late by 2 min. And then it gains 4 min 48 sec. Means we have to cover 2 min time as well as 4 min 4 sec time also.
Therefore total gain = 2 + 24/5 = 34/5 min in 7 days 2 hrs (170 hrs).
Here, extra 2 min of which we are a late need to be covered to make the time correct are gained in.
Therefore 34/5 min = 170.
1 min = 170 * (5/34),
2 min = 2 * 170 * (5/34),
2 min = 50 hrs.
i.e 2 days 2 hrs from Monday which is Wednesday 2 pm.
Therefore total gain = 2 + 24/5 = 34/5 min in 7 days 2 hrs (170 hrs).
Here, extra 2 min of which we are a late need to be covered to make the time correct are gained in.
Therefore 34/5 min = 170.
1 min = 170 * (5/34),
2 min = 2 * 170 * (5/34),
2 min = 50 hrs.
i.e 2 days 2 hrs from Monday which is Wednesday 2 pm.
Sonai said:
9 years ago
Thank you everyone.
Prateek said:
9 years ago
Thank you, @Akash.
Apoorva said:
9 years ago
We added 2 min to 4 min and 48 sec because the word gain was specified.
What can B the variation in question that will make us subtract 2 min from 4 min and 48 sec?
What can B the variation in question that will make us subtract 2 min from 4 min and 48 sec?
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