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 3 of 6.
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?
Meethu said:
6 years ago
(2 min + 4 min 48 seconds)=(408 seconds).
For 170 hours.
For 1 hr (408/170)=2.4 seconds,
For 120 seconds(2 min initially),
Hours=(120/2.4)=50.
So Wednesday 2 PM.
For 170 hours.
For 1 hr (408/170)=2.4 seconds,
For 120 seconds(2 min initially),
Hours=(120/2.4)=50.
So Wednesday 2 PM.
(11)
Sakshi said:
9 years ago
@Piyush,
It's unitary method.
34/5 mins are gained in 170 hrs.
So 1 min is gained in 170 * 5/34 hrs.
So 2 mins are gained in 170 * 5/34 * 2 hrs.
It's unitary method.
34/5 mins are gained in 170 hrs.
So 1 min is gained in 170 * 5/34 hrs.
So 2 mins are gained in 170 * 5/34 * 2 hrs.
Piyush said:
9 years ago
2 min are gained in.
170 x (5/34) x 2 hrs = 50 hrs.
Can you please explain this.
Actually, my question is why we have multiplied "2" here?
170 x (5/34) x 2 hrs = 50 hrs.
Can you please explain this.
Actually, my question is why we have multiplied "2" here?
V.k said:
1 decade ago
There logic behind this is 2 min slow and when we get 2 min slow by fast.
So we get the right time and I hope all other thing will be OK.
So we get the right time and I hope all other thing will be OK.
Ariella said:
1 decade ago
@ Rajesh.
Given that the said watch was 2 minutes low at Monday noon. Hence when it gained 2 minutes, The time was correct.
Given that the said watch was 2 minutes low at Monday noon. Hence when it gained 2 minutes, The time was correct.
Kumar said:
1 decade ago
How to covert 2 min + 4 min and 48 sec by using how to covert 34/5 or 44/5?
Please explain clearly.
Please explain clearly.
Manas said:
1 decade ago
408 sec covered in 170 hrs
1 sec covered in 170/408.
2mins=120 secs covered in 170/408*120=50
1 sec covered in 170/408.
2mins=120 secs covered in 170/408*120=50
GAURAV said:
6 years ago
Finally, I satisfied with the answers of @Akash vashista and Shashank. Thanks, both of them.
(2)
Shree said:
1 decade ago
How to covert 2min+4min 48 sec into 34/5. I am getting it as 26/5? Explain it clearly.
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