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:
156 comments Page 16 of 16.
Brijesh said:
6 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.
Rajat said:
6 years ago
9hrs and 15 minutes =555 and 555/60 = 9.25, but how it is 37/4?
Please explain.
Please explain.
Yogetha said:
6 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).
RESHMA said:
6 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.
Prashasti said:
6 years ago
Well said, Thank you @Sundar.
DRB said:
4 weeks ago
@All.
To those who say option A is correct.
1. Total minutes as per the time shown by the watch from 7.00 am to 4.15 pm
555 minutes.
(these 555 minutes also include the 5 sec. gained by the watch every 3 minutes.
Most people have failed to adjust to the same.)
2. Let's see how to adjust to nullify the 5 seconds gained every three minutes to arrive at the correct answer.
Every three minutes, the watch gains 5 seconds.
3 minutes = 180 seconds.
So, 555minutes * 180/185 =540 minutes.
NOTE: This step can be solved in many different ways. for eg, instead of converting 3 minutes in 180 seconds, you can keep them as it is and instead say gains per minute is 1.66666667 seconds. etc.
3. Final answer 7.00 am + 540 minutes = 4.00 pm.
To those who say option A is correct.
1. Total minutes as per the time shown by the watch from 7.00 am to 4.15 pm
555 minutes.
(these 555 minutes also include the 5 sec. gained by the watch every 3 minutes.
Most people have failed to adjust to the same.)
2. Let's see how to adjust to nullify the 5 seconds gained every three minutes to arrive at the correct answer.
Every three minutes, the watch gains 5 seconds.
3 minutes = 180 seconds.
So, 555minutes * 180/185 =540 minutes.
NOTE: This step can be solved in many different ways. for eg, instead of converting 3 minutes in 180 seconds, you can keep them as it is and instead say gains per minute is 1.66666667 seconds. etc.
3. Final answer 7.00 am + 540 minutes = 4.00 pm.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers