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Between 12:24 and 14:36 the HOUR hand of a clock turns by [#permalink ]
02 Nov 2007, 08:03

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Between 12:24 and 14:36 the HOUR hand of a clock turns by how many degrees?
Between 12:24 and 14:36 the MINUTE hand of a clock turns by how many degrees?

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Between 12:24 and 14:36 the MINUTE hand of a clock turns by how many degrees?

degree per minute = 360/(60*12) = 1/2

2 houres and 12 minutes = 132

132*360/720 = 66

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KillerSquirrel wrote:

Between 12:24 and 14:36 the MINUTE hand of a clock turns by how many degrees?

degree per minute = 360/(60*

12 ) = 1/2

2 houres and 12 minutes = 132

132*360/720 = 66

degree per minute = 360/(60*

12 ) = 1/2

what is this 12 over here??

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sidbidus wrote:

KillerSquirrel wrote:

Between 12:24 and 14:36 the MINUTE hand of a clock turns by how many degrees?

degree per minute = 360/(60*

12 ) = 1/2

2 houres and 12 minutes = 132

132*360/720 = 66

degree per minute = 360/(60*

12 ) = 1/2

what is this 12 over here??

12 hours

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But for the minute hand why do you need hours???
For minute hand...
360 for 1hr or 60 minutes
=> degree/ minute = 360/60 = 6
Am I missing something???
I guess you were explaining for the hour hand

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sidbidus wrote:

But for the minute hand why do you need hours??? For minute hand... 360 for 1hr or 60 minutes => degree/ minute = 360/60 = 6 Am I missing something??? I guess you were explaining for the hour hand

ask yourself - how many minutes are there in 12 hours (clock cycle) ?

60*12 = 720

and ask yourself - how many degrees are in one clock cycle (from 12 to 12) = 360

360/720 = 1/2 degree per minute.

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KillerSquirrel wrote:

sidbidus wrote:

But for the minute hand why do you need hours??? For minute hand... 360 for 1hr or 60 minutes => degree/ minute = 360/60 = 6 Am I missing something??? I guess you were explaining for the hour hand

ask yourself - how many minutes are there in 12 hours (clock cycle) ?

60*12 = 720

and ask yourself - how many degrees are in one clock cycle (from 12 to 12) = 360

360/720 = 1/2 degree per minute.

pretty well explained

KS, for the hour hand, are the minute and hour hands the same answer with 66 degrees?

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sidbidus wrote:

KillerSquirrel wrote:

sidbidus wrote:

But for the minute hand why do you need hours??? For minute hand... 360 for 1hr or 60 minutes => degree/ minute = 360/60 = 6 Am I missing something??? I guess you were explaining for the hour hand

ask yourself - how many minutes are there in 12 hours (clock cycle) ?

60*12 = 720

and ask yourself - how many degrees are in one clock cycle (from 12 to 12) = 360

360/720 = 1/2 degree per minute.

That's for the hour hand ur talking about........right??

See attachment

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beckee529 wrote:

KillerSquirrel wrote:

sidbidus wrote:

But for the minute hand why do you need hours??? For minute hand... 360 for 1hr or 60 minutes => degree/ minute = 360/60 = 6 Am I missing something??? I guess you were explaining for the hour hand

ask yourself - how many minutes are there in 12 hours (clock cycle) ?

60*12 = 720

and ask yourself - how many degrees are in one clock cycle (from 12 to 12) = 360

360/720 = 1/2 degree per minute.

pretty well explained

KS, for the hour hand, are the minute and hour hands the same answer with 66 degrees?

Yes the same for the hour hand.

360/12 = 30

30*(two hours and 1/5 of an hour) = 30*11/5 = 66

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KillerSquirrel wrote:

beckee529 wrote:

KillerSquirrel wrote:

sidbidus wrote:

But for the minute hand why do you need hours??? For minute hand... 360 for 1hr or 60 minutes => degree/ minute = 360/60 = 6 Am I missing something??? I guess you were explaining for the hour hand

ask yourself - how many minutes are there in 12 hours (clock cycle) ?

60*12 = 720

and ask yourself - how many degrees are in one clock cycle (from 12 to 12) = 360

360/720 = 1/2 degree per minute.

pretty well explained

KS, for the hour hand, are the minute and hour hands the same answer with 66 degrees?

Yes the same for the hour hand.

360/12 = 30

30*(two hours and 1/5 of an hour) =

30*11/5 = 66
good.. thats exactly how i solved

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6 degrees each minute 30 degrees each hour
solving for the hour hand,
it moved 2 hours and 12 minutes. 12 minutes is 1/5 of an hour or 1/5 of 30 degrees.
2* 30 + 1/5(30)
60+6
66
solving for minutes
the timeframe was 2 hours 12 minutes. we can disregard the 2 hours since it will be in the same position.
12*6 degrees each minute.
72 minutes

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bmwhype2 wrote:

6 degrees each minute 30 degrees each hour solving for the hour hand, it moved 2 hours and 12 minutes. 12 minutes is 1/5 of an hour or 1/5 of 30 degrees. 2* 30 + 1/5(30) 60+6 66 solving for minutes the timeframe was 2 hours 12 minutes. we can disregard the 2 hours since it will be in the same position. 12*6 degrees each minute. 72 minutes

the red segment is wrong.

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KillerSquirrel wrote:

bmwhype2 wrote:

6 degrees each minute 30 degrees each hour solving for the hour hand, it moved 2 hours and 12 minutes. 12 minutes is 1/5 of an hour or 1/5 of 30 degrees. 2* 30 + 1/5(30) 60+6 66 solving for minutes the timeframe was 2 hours 12 minutes. we can disregard the 2 hours since it will be in the same position. 12*6 degrees each minute. 72 minutes

the red segment is wrong.

what i mean is

360/60 divisions or minutes = 6 degrees

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The hours hand has a gain of 1/2 degree ever 1 minute.....
so for (36-24)min it has a 6 degree gain.
The minute hand gains 6 degree for every 1 minute.....
so for (36-24)minutes it gains 12*6=72 degrees

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Re: Clock question [#permalink ]
03 Nov 2007, 22:24

bmwhype2 wrote:

Between 12:24 and 14:36 the HOUR hand of a clock turns by how many degrees? Between 12:24 and 14:36 the MINUTE hand of a clock turns by how many degrees?

1 minute is 360/60 = 6 degree

So minute hand turned 36-24 = 12*6 = 72 degree

For hour hand, it is a bit tricky because the hour hand also move according to minute hand.

1 hour = 360/12 = 30 degree

At 12.24, the hour hand is at 24/60 * 30 = 12 degree from 12 pm

At 14.36, the hour hand is at 36/60 * 30 = 18 degree from 14 pm = 30+30+18 = 78 degree from 12 pm

Therefore, total gain = 78-12 = 66 degree

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Re: Between 12:24 and 14:36 the HOUR hand of a clock turns by [#permalink ]
21 Jul 2014, 21:59

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Re: Between 12:24 and 14:36 the HOUR hand of a clock turns by [#permalink ]
21 Jul 2014, 22:00

Do clock and calendar questions appear in gmat?

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Re: Between 12:24 and 14:36 the HOUR hand of a clock turns by [#permalink ]
22 Jul 2014, 02:26

Re: Between 12:24 and 14:36 the HOUR hand of a clock turns by
[#permalink ]
22 Jul 2014, 02:26