Aptitude - Clock - Discussion
Discussion Forum : Clock - General Questions (Q.No. 3)
3.
A clock is started at noon. By 10 minutes past 5, the hour hand has turned through:
Answer: Option
Explanation:
Angle traced by hour hand in 12 hrs = 360°.
| Angle traced by hour hand in 5 hrs 10 min. i.e., | 31 | hrs = |  |
360 | x | 31 |  |
° | = 155°. |
| 6 | 12 | 6 |
Discussion:
87 comments Page 2 of 9.
Narendran, S S said:
1 decade ago
Angle between hr and min is given by
A =30*hr~(11/2)*min
= 30*5 - (11/2)*10
= 95 degrees
Now the angle swiped by the min hand alone is
6 degrees per min
hence 60 degrees per 10 min
Angle swiped by hr hand alone is
A+60 = 95+60 = 155 degrees.
A =30*hr~(11/2)*min
= 30*5 - (11/2)*10
= 95 degrees
Now the angle swiped by the min hand alone is
6 degrees per min
hence 60 degrees per 10 min
Angle swiped by hr hand alone is
A+60 = 95+60 = 155 degrees.
Navaneetha krishnan said:
1 decade ago
Sir i can't understand that 155 degree for which timing?
Vinay said:
1 decade ago
It is for 5 hours 10 minutes from noon (12).
Shravan purohit said:
1 decade ago
@navaneetha
Given : our hour hand started at noon i.e. 12 o'clock
and 10 minutes past 5 i.e. 5 hour 10 minutes
we find angle between 12 and 5.10 o'clock
firstly we convert 5hour 10min into minitus 5*60+10=310min
and 310min convert into hour 310/60=31/6
In 12h = 360
So in 31/6 h= (360/12)(31/6)=155 degree.
Given : our hour hand started at noon i.e. 12 o'clock
and 10 minutes past 5 i.e. 5 hour 10 minutes
we find angle between 12 and 5.10 o'clock
firstly we convert 5hour 10min into minitus 5*60+10=310min
and 310min convert into hour 310/60=31/6
In 12h = 360
So in 31/6 h= (360/12)(31/6)=155 degree.
(1)
Kranti said:
1 decade ago
Very nice explanatoin given by shravan.
Madesh said:
1 decade ago
Don't worry I will explain Clearly....
Past 5 means 5 hours.. and 10 mins out of 60 mins.. that's (10/60)
So.. 5hrs + 10 mins= 5+(10/60) = 5+(1/6).. so. 6*5+1= 31/6hrs..
1hr= 30 degree... so 5hrs= 150 degree and that past 5(means 5degree)...
So 150+5 = 155.
Past 5 means 5 hours.. and 10 mins out of 60 mins.. that's (10/60)
So.. 5hrs + 10 mins= 5+(10/60) = 5+(1/6).. so. 6*5+1= 31/6hrs..
1hr= 30 degree... so 5hrs= 150 degree and that past 5(means 5degree)...
So 150+5 = 155.
Leenus said:
1 decade ago
I can't understand "by 10 mins past 5".
Sasidhar said:
1 decade ago
Here angle In 12h is = 360 degree
angle in 10 PAST 5 means 5:10
h=5, m=10
Now
|30h-11/2m|= degree
|30*5-11/2*10| = 95 degree
Now degree=360-95=155 degree. Got it friends?
angle in 10 PAST 5 means 5:10
h=5, m=10
Now
|30h-11/2m|= degree
|30*5-11/2*10| = 95 degree
Now degree=360-95=155 degree. Got it friends?
Mary said:
1 decade ago
Its easy
1hr=30 degree
ie 5hr=5*30=150 degree
also
10 min=10/60hr=1/6hr
we know 1hr=30 degree
ie
(1/6)*30=5 degree
so 150 deg+5 deg=155 deg.
its solved :)
1hr=30 degree
ie 5hr=5*30=150 degree
also
10 min=10/60hr=1/6hr
we know 1hr=30 degree
ie
(1/6)*30=5 degree
so 150 deg+5 deg=155 deg.
its solved :)
Sowmya said:
1 decade ago
How can it be 360-95=155? it is 265. I don't understand the logic.
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