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 2 of 6.
Siddhant said:
6 years ago
How we are getting after calculation 4min 48 sec in denominator i.e. (5?).
I understood 4*60=240 but I am not getting that how 5 came in the denominator.
Please, anyone help me. Thanks.
I understood 4*60=240 but I am not getting that how 5 came in the denominator.
Please, anyone help me. Thanks.
(1)
Koya said:
8 years ago
Sam sets alarm at 5 am. But the clock loses 16 minutes in 24 hours. Effectively, the clock indicates 10:00 pm on the 4th day. Find out the original time of the clock.
Tell me the answer for this question.
Tell me the answer for this question.
(1)
Malli said:
1 decade ago
Please anybody explain me the gain and loose concept of the clock. I thought we should subtract 2 mins from 4 mins 4 sec. So we can calculate actual gain, so how we add both loss and gain of time >?
(1)
Menaga said:
8 years ago
Thank you everyone.
Moni said:
7 years ago
Explain me clearly to get it.
Karthik said:
8 years ago
Gain means the clock's hands are moving fast than actual time (i.e it takes less than 60minutes for minute's hand to complete 360 degrees).
Initially, the time in given clock is 11:58am but the actual time is 12 pm (this might be because someone changed the time to 11:58 in given clock).
Since the clock is moving fast it's time is 4min 48sec fast on following Monday. Now at one point in between present Monday to next Monday the given clock's time coincides with normal clock's time (i.e correct time). Now total time from 12 pm to next Monday 2pm is 170hours. Total time gain by given clock = 2+ (4min 48sec) = 34/5min in 170 hours. What we need now is 'When it shows the correct time. ' If clock gains those 2minutes which it is lagging initially then it shows the correct time. 34/5min gain in 170hours then 2min will gain in 170*2* (5/34) hours.
Initially, the time in given clock is 11:58am but the actual time is 12 pm (this might be because someone changed the time to 11:58 in given clock).
Since the clock is moving fast it's time is 4min 48sec fast on following Monday. Now at one point in between present Monday to next Monday the given clock's time coincides with normal clock's time (i.e correct time). Now total time from 12 pm to next Monday 2pm is 170hours. Total time gain by given clock = 2+ (4min 48sec) = 34/5min in 170 hours. What we need now is 'When it shows the correct time. ' If clock gains those 2minutes which it is lagging initially then it shows the correct time. 34/5min gain in 170hours then 2min will gain in 170*2* (5/34) hours.
Tamizharasi said:
8 years ago
Thank you all for the given explanation.
Anu said:
8 years ago
Very helpful. Thanks a lot @Akash.
Sakshi said:
8 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?
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers