Aptitude - Clock - Discussion
Discussion Forum : Clock - General Questions (Q.No. 4)
4.
A watch which gains 5 seconds in 3 minutes was set right at 7 a.m. In the afternoon of the same day, when the watch indicated quarter past 4 o'clock, the true time is:
Answer: Option
Explanation:
| Time from 7 a.m. to 4.15 p.m. = 9 hrs 15 min. = | 37 | hrs. |
| 4 |
3 min. 5 sec. of this clock = 3 min. of the correct clock.
 |
37 | hrs of this clock = | 1 | hrs of the correct clock. |
| 720 | 20 |
| |
37 | hrs of this clock = |  |
1 | x | 720 | x | 37 |  |
hrs of the correct clock. |
| 4 | 20 | 37 | 4 |
= 9 hrs of the correct clock.
The correct time is 9 hrs after 7 a.m. i.e., 4 p.m.
Discussion:
154 comments Page 3 of 16.
RESHMA said:
5 years ago
@Mamta.
Your explanation is quite easy for me to understand. Thanks for helping.
Your explanation is quite easy for me to understand. Thanks for helping.
Yogetha said:
5 years ago
@Rajat.
555/60=9.25 that can be written in fractional form by simplifying it as 37/4 since (15*37=555 & 15*4=60).
555/60=9.25 that can be written in fractional form by simplifying it as 37/4 since (15*37=555 & 15*4=60).
Rajat said:
5 years ago
9hrs and 15 minutes =555 and 555/60 = 9.25, but how it is 37/4?
Please explain.
Please explain.
Brijesh said:
5 years ago
Use this formula.
(60*hour -11*minutes)/2 by this will get angle btw hour and minute hand.
Then we know the hour hand is leading so add minute hand will get an answer.
(60*hour -11*minutes)/2 by this will get angle btw hour and minute hand.
Then we know the hour hand is leading so add minute hand will get an answer.
Malini said:
5 years ago
Why we reciprocal it 37÷720? Please explain me.
Shashi said:
6 years ago
We know that 9hr+15min, by converting it in min we get 540+15 = 555min-----eqn1.
To get 3 min parts, we divide 555/3 = 185.
Or we can say we have 185, 3 min.
Multiplying 185 * 5sec (by converting it into min ie 5/60) = 185* (5/60) = 15min.
So distracting 555min - 15min=540.
Or 4hr:15min - 15min = 4hr or 4o'clock.
To get 3 min parts, we divide 555/3 = 185.
Or we can say we have 185, 3 min.
Multiplying 185 * 5sec (by converting it into min ie 5/60) = 185* (5/60) = 15min.
So distracting 555min - 15min=540.
Or 4hr:15min - 15min = 4hr or 4o'clock.
Piyush said:
6 years ago
3min 5sec = 3min.
6min 10sec = 6min.
Similary 1hr = 1hr 1min 40sec.
Calculation:
6*10min = 6*10min 10*10sec
60 min = 60 min 100 sec(61min 40 sec)
So, total gain 1hour = 1min 40 sec.
Time between 7 am to 4.15 pm= 9hr 15 min.
In 9hr 15 min time gain will we 15min because;
9*1min 40 sec=> 9min + 360sec =>9 min + 6min =>15min.
So the correct time in the clock is 4 pm.
And gain in remaining 15 min =25sec (5*5).
25 sec can be neglected.
Hence the correct answer option B.
6min 10sec = 6min.
Similary 1hr = 1hr 1min 40sec.
Calculation:
6*10min = 6*10min 10*10sec
60 min = 60 min 100 sec(61min 40 sec)
So, total gain 1hour = 1min 40 sec.
Time between 7 am to 4.15 pm= 9hr 15 min.
In 9hr 15 min time gain will we 15min because;
9*1min 40 sec=> 9min + 360sec =>9 min + 6min =>15min.
So the correct time in the clock is 4 pm.
And gain in remaining 15 min =25sec (5*5).
25 sec can be neglected.
Hence the correct answer option B.
Piyush said:
6 years ago
3min 5sec = 3min.
6min 10sec = 6min.
Similary 1hr = 1hr 1min 40sec.
Calculation:
6*10min = 6*10min 10*10sec
60 min = 60 min 100 sec(61min 40 sec)
So, total gain 1hour = 1min 40 sec.
Time between 7 am to 4.15 pm= 9hr 15 min.
In 9hr 15 min time gain will we 15min because;
9*1min 40 sec=> 9min + 360sec =>9 min + 6min =>15min.
So the correct time in the clock is 4 pm.
And gain in remaining 15 min =25sec (5*5).
25 sec can be neglected.
Hence the correct answer option B.
6min 10sec = 6min.
Similary 1hr = 1hr 1min 40sec.
Calculation:
6*10min = 6*10min 10*10sec
60 min = 60 min 100 sec(61min 40 sec)
So, total gain 1hour = 1min 40 sec.
Time between 7 am to 4.15 pm= 9hr 15 min.
In 9hr 15 min time gain will we 15min because;
9*1min 40 sec=> 9min + 360sec =>9 min + 6min =>15min.
So the correct time in the clock is 4 pm.
And gain in remaining 15 min =25sec (5*5).
25 sec can be neglected.
Hence the correct answer option B.
Snehashish Das said:
6 years ago
Here seeing so many controversies, I would suggest that if we take the exact accurate value of 925/60.
Then that is equal to 925/60=15.4166666667(if we take 15.41).
Simplification 185/12 that mean 15 and 5/12 part minute.
9 hrs= 9x60=540 min --- 185/12min = 524.58 min.
that means 3 hrs.59 min.35 sec.= 7/12 past 3.
Then that is equal to 925/60=15.4166666667(if we take 15.41).
Simplification 185/12 that mean 15 and 5/12 part minute.
9 hrs= 9x60=540 min --- 185/12min = 524.58 min.
that means 3 hrs.59 min.35 sec.= 7/12 past 3.
K.ROSHANRAJ said:
6 years ago
For every 3 mins 5 sec is gained so totally from 7.am to 4.15 pm there is an excess of 15 mins.
So subtract that 15 with the 4.15 pm,
And the answer will be at 4 pm.
So subtract that 15 with the 4.15 pm,
And the answer will be at 4 pm.
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