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:
155 comments Page 10 of 16.
Akhil Sunder said:
1 decade ago
How 37/720 is changed to 720/37?
Sachin said:
1 decade ago
A clock is showing 14:19, what will time after 14399999991 min.
Pooja said:
1 decade ago
From 7 am to 4 pm, We are getting 900 sec gain, which is 900/60 = 15 min gain.
Now, the question has asked what will be the actual time when it is showing 4:15 pm.
Now, at 4 pm it already has gained 15 min, i.e. it is showing 4:15 pm already.
I was doing it wrong when I took 900 + 25 sec, where 25 sec was for 4 to 4:15 pm, which is wrong.
We are not asked to calculate time at 4:15 pm, we are asked for 4 pm.
Now, the question has asked what will be the actual time when it is showing 4:15 pm.
Now, at 4 pm it already has gained 15 min, i.e. it is showing 4:15 pm already.
I was doing it wrong when I took 900 + 25 sec, where 25 sec was for 4 to 4:15 pm, which is wrong.
We are not asked to calculate time at 4:15 pm, we are asked for 4 pm.
(1)
Kasinath@Hyd said:
1 decade ago
7am to 4:15====>is 9hrs and 15 min.
3min ====EXCEEDS===> 5sec.
15min==============> 25sec equation (1).
1hr (60min) =========> 100sec.
====================
======So on=========
====================
9hr=================> 900sec equation (2).
9:15 == equation(1)+equation(2) => 925 sec i.e. in 9:15 min time exceeded by 15 min.
Therefore time is 4 pm and not 4:15.
3min ====EXCEEDS===> 5sec.
15min==============> 25sec equation (1).
1hr (60min) =========> 100sec.
====================
======So on=========
====================
9hr=================> 900sec equation (2).
9:15 == equation(1)+equation(2) => 925 sec i.e. in 9:15 min time exceeded by 15 min.
Therefore time is 4 pm and not 4:15.
Vivek said:
1 decade ago
Correct answer is (A).
In 3 min fast is - 5 sec.
In 1 min fast is - 5/3 sec.
In 60 min fast is - 5/3*60 - 100 sec.
So 1 hr fast is - 100 sec.
In 9 hr 25 sec - 925 sec.
Si actually fast is - 900 sec + 25 sec = 900/60+25/60 = 15 5/12 min.
So actual time is = 3 hr 59*7/12.
In 3 min fast is - 5 sec.
In 1 min fast is - 5/3 sec.
In 60 min fast is - 5/3*60 - 100 sec.
So 1 hr fast is - 100 sec.
In 9 hr 25 sec - 925 sec.
Si actually fast is - 900 sec + 25 sec = 900/60+25/60 = 15 5/12 min.
So actual time is = 3 hr 59*7/12.
Sasi said:
1 decade ago
For 3 mins 5 sec gain.
i.e for 180 sec clock shows 185 sec.
That means for every hour it's shows 1 min 40 sec more than actual time.
We need to calculate actual time when clock shows 4:15 pm.
Given that time set at 7 am so the difference between 7 to 4:15 is 9:15 hours.
Clock showing us 1 min 40 secs more for every hour then for 9 hours 15 secs it shows 15 mins fast.
So the answer is 4 pm.
i.e for 180 sec clock shows 185 sec.
That means for every hour it's shows 1 min 40 sec more than actual time.
We need to calculate actual time when clock shows 4:15 pm.
Given that time set at 7 am so the difference between 7 to 4:15 is 9:15 hours.
Clock showing us 1 min 40 secs more for every hour then for 9 hours 15 secs it shows 15 mins fast.
So the answer is 4 pm.
Sai kumar said:
1 decade ago
3 past 5 seconds = 3 mins. There is no such one in the question.
How you took that one? Can you explain clearly?
How you took that one? Can you explain clearly?
Javad said:
1 decade ago
Leave all worries guys think practically.
For 3 min 5 sec gain.
Then for 15 min 25 sec, for 1 hour 100 sec i.e. 1.5 min and 10 sec.
For 9 hr 15 min it is 13.5 (i.e. 1.5*9) + 1.5 (i.e. Remaining 10 sec*9).
So totally 13.5+1.5= 15 min gain.
That is 4op o'clock.
For 3 min 5 sec gain.
Then for 15 min 25 sec, for 1 hour 100 sec i.e. 1.5 min and 10 sec.
For 9 hr 15 min it is 13.5 (i.e. 1.5*9) + 1.5 (i.e. Remaining 10 sec*9).
So totally 13.5+1.5= 15 min gain.
That is 4op o'clock.
Ankita said:
1 decade ago
How 37/4 becomes not understood?
Anaj Hussain said:
1 decade ago
How we got 37/720 ? please tell me any one.
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