Aptitude - Clock - Discussion

@B.Vamsi Srinivas

final result you have to subtract from 360degree's
now
i mean yoy got finally 162 1\2
360-162 1\2=197 1\2

this is simple processes.

I don't know people are so confused over these small problem let me make you all clear. Hear we know 60 min = 360 degree.

& 12 hrs =360 degree.

When time is 10.25 it means hour hand is slight ahead 10 not exactly at 10 so 10.25 = 125/12 as said earlier so calculating angle using hour relation by unitary method its getting 312.5.

Now calculate the angle made by minute hand i.e 25 minutes it makes (360=60) *25=150 draw a clock and see the angle made by hour that is 312. 5 degree from 12 o clock and similarly see the angle made by minute hand its 150 degree from 12 0 clock here if reflex angle is asked so which is angle made by them in anticlockwise direction. Since clock rotates in clock wise direction. If you are not getting reflex angle just remember as anticlockwise concept. Hope you get it my friend.

Hey friends,

Reflex angle simply means opposite angle, for solving this problem first of all we have to find out the angle made between 10:25. After than this angle is subtracted in 360.

Angle made b/w 10:25 == (360/12 x 10 + 25 x 1/2) - 25x6 = 325/2

Than reflexive angle == (360 - 325/2) = 395/2 = 197,1/2

So, Ans(D).

Hey guys.

Reflex angle is nothing but the exterior angle.i.e. you got to subtract your angle with 360.
Here:
Using the formula : 30*h-11/2*m
30*10-11/2*25=162.5.

Reflex angle = 360-162.5 = 197.5.

Angle between 2 hands = 30 hours - 11/2 minutes
= 30 (10)- 11/2 (25)
=162.5 degree

Reflex angel = 360 - angle between 2 hands
= 197.5

It can even be solved like this:
HOUR HAND:
For 1 hour, i.e., 60min angle covered by hour hand =360/12=30deg
For 25 min= (30*25/60) (cross multiply)= 12.5 deg.

Minute hand:
It goes from 10 and stops at 5 for 10.25
Therefore angle covered=(360*7/12)=210

Now subtact angle moved by minute hand from hour hand
210-12.5= 197.5 deg.

If have to calculate angle at time hh:mm
Use formala as
Angle=|30(hh)-11/2(mm)|

To calculate calculate reflex angle use

Reflex Angle= 360-|30(hh)-11/2(mm)|

Short hand or hour hand = 360/12 = 30
Long hand or minute hand= 360/60 = 6
When 10.25 is the short hand in the clock then 10x30=300 and 25x30/60=12.5
Adding this 300+12.5=312.5
When 25 minute long hand is 25x6=150
=360-[312.5-150]=197.5.

THERE IS A READY MADE FORMULA FOR THIS KIND OF PROBLEM:

1/2(60H-11M).

WHERE ,
H = HOUR
M = MINUTE.

Eg:10.30 can be written as
1/2(60*10-11*30).

As per problem.
1/2(60*10-11*25)
= 1/2(600-375)
= 1/2(325)
= 162.5.

In question it is asked reflex angle so,
= 360 - 162.5.
= 197.5.

How is the angle traced by hours hand is 125/12.