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 2 of 16.
Kiran said:
3 years ago
5sec gains in 3min.
5sec =3 min.
Multiply with 20.
100 sec gains in 60min(100sec = 60min).
Then 300sec = 180min.
Converting 300 sec into min is 5min.
180min is 3 hrs.
So it gains 5min in 3hrs.
We know that from 7 to 4 .15min is 9hrs 15min.
It gains 5min in 3hrs then for 9hrs it gains 15min so subtract 15 min from the time.
Then the answer is 4'pm.
5sec =3 min.
Multiply with 20.
100 sec gains in 60min(100sec = 60min).
Then 300sec = 180min.
Converting 300 sec into min is 5min.
180min is 3 hrs.
So it gains 5min in 3hrs.
We know that from 7 to 4 .15min is 9hrs 15min.
It gains 5min in 3hrs then for 9hrs it gains 15min so subtract 15 min from the time.
Then the answer is 4'pm.
(55)
Puppireddy Sai Krishna said:
3 years ago
If the clock gains 5sec for every 3mins it travels 9hrs and 15mins i.e., 9.25hrs.
Let the actual clock goes 'x' 3mins.
Then the clock which gains 5 secs for every 3 mins will go (3mins)x + (5secs)x =9.25hrs
=> (3+ (5/60))x = 9.25*60.
So x= 180mins,
i.e., x=3hrs,
So the actual clock goes 3x i.e., 9hrs.
So, 9hrs from 7 a.m. is 4 p.m.
Let the actual clock goes 'x' 3mins.
Then the clock which gains 5 secs for every 3 mins will go (3mins)x + (5secs)x =9.25hrs
=> (3+ (5/60))x = 9.25*60.
So x= 180mins,
i.e., x=3hrs,
So the actual clock goes 3x i.e., 9hrs.
So, 9hrs from 7 a.m. is 4 p.m.
(8)
Mervin said:
3 years ago
3 min = 3+ 5/60 min = 3+1/12 = 37/12 min.
quarter past = 15 min.
7am-4:15pm = 9hr 15 min= 9 x 60+15=555min.
for 37/12 min = 3 min,
for 555min = ?
540min.
540/60 = 9hr,
7am + 9h = 4pm.
quarter past = 15 min.
7am-4:15pm = 9hr 15 min= 9 x 60+15=555min.
for 37/12 min = 3 min,
for 555min = ?
540min.
540/60 = 9hr,
7am + 9h = 4pm.
(12)
Rutvik Dalal said:
4 years ago
Clock gains 5 seconds every 3 minutes = 100 seconds every hour (60 minutes) = 900 seconds every 9 hours = 15 minutes every 9 hours.
Hence when the faulty clock shows 4:15 PM, the actual clock should show 15 minutes less i.e. 4:00 PM.
Hence when the faulty clock shows 4:15 PM, the actual clock should show 15 minutes less i.e. 4:00 PM.
(29)
Rohit said:
4 years ago
925/60 is not equal to 15, it is equal to 15 5/12 and you subtracted the 15 min but what about 25 sec? Please explain.
(13)
Karthik said:
4 years ago
Watch gain 5 sec each 3min.
1-hour watch gain 100sec.
100x9 =900 further 15 min watch gain 25sec if we divided 925/60 we get 15 min we minus 15 min from 4.15 we get 4.00.
1-hour watch gain 100sec.
100x9 =900 further 15 min watch gain 25sec if we divided 925/60 we get 15 min we minus 15 min from 4.15 we get 4.00.
(7)
Alya said:
4 years ago
Crt time: 3mins wrong time: 3mins 5 seconds.
So 1 hr = 1hr 100 seconds wrong time.
7:00 Am to 4:15 PM = 9 hrs 15 mins difference,
For 9 hr 15 mins = 9 hr 925 sec wrong time,
Subtract 925 sec (900sec = 15 mins)from 4: 15 PM
So, the ANSWER is 4:00 PM.
So 1 hr = 1hr 100 seconds wrong time.
7:00 Am to 4:15 PM = 9 hrs 15 mins difference,
For 9 hr 15 mins = 9 hr 925 sec wrong time,
Subtract 925 sec (900sec = 15 mins)from 4: 15 PM
So, the ANSWER is 4:00 PM.
(4)
Neci said:
4 years ago
Clock gains 5 seconds every 3 minutes = 100 seconds every hour (60 minutes) = 900 seconds every 9 hours = 15 minutes every 9 hours.
Hence, when the faulty clock shows 4:15 PM, the actual clock should show 15 minutes less i.e. 4:00 PM.
Hence, when the faulty clock shows 4:15 PM, the actual clock should show 15 minutes less i.e. 4:00 PM.
(3)
Rishabh said:
4 years ago
Thanks for explaining @Sundar.
Prashasti said:
5 years ago
Well said, Thank you @Sundar.
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