Aptitude - Clock - Discussion
Discussion Forum : Clock - General Questions (Q.No. 5)
5.
How much does a watch lose per day, if its hands coincide every 64 minutes?
Answer: Option
Explanation:
55 min. spaces are covered in 60 min.
| 60 min. spaces are covered in |  |
60 | x 60 |  min. |
= 65 | 5 | min. |
| 55 | 11 |
| Loss in 64 min. = | |
65 | 5 | - 64 | |
= | 16 | min. |
| 11 | 11 |
| Loss in 24 hrs = | |
16 | x | 1 | x 24 x 60 | min. |
= | 32 | 8 | min. |
| 11 | 64 | 11 |
Discussion:
119 comments Page 3 of 12.
Shivangi said:
1 decade ago
The universal rule is , hands of any accurate clock meets after 65 5/11 [=(11*65+5)/11] minutes.
But here the clock is taking 64 minutes to meet !
Hence , the error is [65 5/11]-[64] mints -> 16/11 minutes .
Now , total minutes in a day is = 24 hrs* 60 minutes= 1440 minutes.
Now, we know , the error in 64 mins was --> 16/11.
Means in 1 min ---> 16/11*1/64.
So in 11440 mins---> (16/11*1/64)*11440.
Which equals to ---> 360/11 Answer.
But here the clock is taking 64 minutes to meet !
Hence , the error is [65 5/11]-[64] mints -> 16/11 minutes .
Now , total minutes in a day is = 24 hrs* 60 minutes= 1440 minutes.
Now, we know , the error in 64 mins was --> 16/11.
Means in 1 min ---> 16/11*1/64.
So in 11440 mins---> (16/11*1/64)*11440.
Which equals to ---> 360/11 Answer.
(1)
Sonam said:
1 decade ago
Gain or loss per day = (720/11-m) (60*24/m).
M: Interval at which minute hand overtake the hour hand.
If result positive indicate positive otherwise negative.
= (720/11-64) (60*24/64).
= (16/11) (60*24/64).
= 32 (8/11).
M: Interval at which minute hand overtake the hour hand.
If result positive indicate positive otherwise negative.
= (720/11-64) (60*24/64).
= (16/11) (60*24/64).
= 32 (8/11).
(1)
Ankit said:
9 years ago
Why we multiply it by 1/64?
(1)
Karan singh saud said:
9 years ago
Very simple question.
A clock coincides 11 times in 12 hrs (720 min).
So, per meeting =720/11 (65.45).
i.e hands coincide after every 65.45 min.
But according to the question. Hands coincide every 64 min.
So clock losses 1.45 min for every meeting.
And we know that hands coincide 22 times a day.
So. Answer = 22 * 1.45. (I guess this is correct).
A clock coincides 11 times in 12 hrs (720 min).
So, per meeting =720/11 (65.45).
i.e hands coincide after every 65.45 min.
But according to the question. Hands coincide every 64 min.
So clock losses 1.45 min for every meeting.
And we know that hands coincide 22 times a day.
So. Answer = 22 * 1.45. (I guess this is correct).
(1)
Akgarhwal said:
9 years ago
Watch coincide every 65 5/11 min
Loss in 64 minutes= (65 5/11- 64)= 16/11
Loss in 1 minute= (16/11) * (1/64)
Loss in 60 minute or 1 hr = (16/11) * (1/64) * 60,
Loss in a day or 24 hours = (16/11) * (1/64) * 60 * 24 = 32 8/11 min.
Loss in 64 minutes= (65 5/11- 64)= 16/11
Loss in 1 minute= (16/11) * (1/64)
Loss in 60 minute or 1 hr = (16/11) * (1/64) * 60,
Loss in a day or 24 hours = (16/11) * (1/64) * 60 * 24 = 32 8/11 min.
(1)
Anand S Moghe said:
9 years ago
I have a small correction to offer to my previous explanation.
In 64 mins of correct time, the watch shows to have covered 65.5/11 mins. So the watch runs faster. Hence the time is gained. In 64 mins the time gained is 1.5/11 min. So in 24 hrs (1440 mins) the time gained is 1440*(16/11)*(1/64) = 32.8/11 mins.
So the time is GAINED, not lost, as per my understanding.
In 64 mins of correct time, the watch shows to have covered 65.5/11 mins. So the watch runs faster. Hence the time is gained. In 64 mins the time gained is 1.5/11 min. So in 24 hrs (1440 mins) the time gained is 1440*(16/11)*(1/64) = 32.8/11 mins.
So the time is GAINED, not lost, as per my understanding.
(1)
Arana said:
8 years ago
Please explain me why in last step it is multiplied with 1/64?
(1)
Saviour24 said:
7 years ago
Why we multiply 1/64 at the end? Please explain.
(1)
Jay said:
7 years ago
2 hands coincide after 65+5/11 minutes in real but here it is 64 minutes.
(Coincident. Two lines or shapes that lie exactly on top of each other)
which means 1+5/11 lose per hour.
this coincides happen 22 times in a day.
which means total lost per day (1+5/11)*22=32 min.
(Coincident. Two lines or shapes that lie exactly on top of each other)
which means 1+5/11 lose per hour.
this coincides happen 22 times in a day.
which means total lost per day (1+5/11)*22=32 min.
(1)
Tiwari said:
7 years ago
Use this formula for solving this.
(720/11-M)(60*24/M).
(720/11-M)(60*24/M).
(1)
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