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 10 of 16.
Tejas said:
9 years ago
Total hours with error from 7 am to 4:15 pm = 9 h 15 min = 33300 secs.
Total original hours from 7 am to 4 pm = 9 hrs = 32400 secs.
Therefore, 33300 - 32400 = 900.
900/60 = 15 min.
Total original hours from 7 am to 4 pm = 9 hrs = 32400 secs.
Therefore, 33300 - 32400 = 900.
900/60 = 15 min.
Vivek said:
9 years ago
No Need to use such a long method.
In 3 mins it's gaining 5 sec.
Io in 1 min the gain take = 5/3.s
And in 60 min it's going to gain = (5/3) * 60= 100 s.
Now the difference between two times is 9 : 15 hrs.
And in 9 hrs it's going to gain 100 * 9 = 900 s.
900 /60 = 15 min.
So at 4 : 15 it's already 15 min ahead so real time will be 4.
In 3 mins it's gaining 5 sec.
Io in 1 min the gain take = 5/3.s
And in 60 min it's going to gain = (5/3) * 60= 100 s.
Now the difference between two times is 9 : 15 hrs.
And in 9 hrs it's going to gain 100 * 9 = 900 s.
900 /60 = 15 min.
So at 4 : 15 it's already 15 min ahead so real time will be 4.
Gjm said:
9 years ago
Simple friends time 7 am to 4.15 pm.
1st we take time 7am to 8am that means 60 min but give its gain 5 sec in 3 min so 60/3 = 20 mins.
Then 20 min * 5 sec = 100 sec that means 1.40 min per 1 hour so now we calculate 7am to 4:15pm, 9 hours = 15 min 4:15 - 0:15 = 4 pm.
1st we take time 7am to 8am that means 60 min but give its gain 5 sec in 3 min so 60/3 = 20 mins.
Then 20 min * 5 sec = 100 sec that means 1.40 min per 1 hour so now we calculate 7am to 4:15pm, 9 hours = 15 min 4:15 - 0:15 = 4 pm.
Yashpal said:
9 years ago
Agree with you @Nitin.
The correct answer is A.
The correct answer is A.
Yashpal said:
9 years ago
You are totally wrong @Gjm.
You can't multiple two different units of time without converting them i.e. 20 min * 5 sec = 100 sec is not possible it could be (20 min/60) sec * 5 sec = whatever.
You can't multiple two different units of time without converting them i.e. 20 min * 5 sec = 100 sec is not possible it could be (20 min/60) sec * 5 sec = whatever.
Sarthak said:
9 years ago
185 seconds to 9hr 15 minute how?
Durgesh said:
9 years ago
A clock is set right at 10 a.m the clock gains 10 minutes in 24 hours .what will be the true time when the clock indicates 3 p.m the following day?
Please solve it.
Please solve it.
Rijas Das said:
9 years ago
Why are you calculating it in the hour? why not in minutes?
Both the answers are different. Make it clear.
Both the answers are different. Make it clear.
Ashok Apple said:
8 years ago
Thank you @Natasha.
Sushma said:
8 years ago
Nice explanation, Thank you @Sundar.
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