A clock is started at noon. By 20 minutes past 4, the hour hand has turned through how many degrees?

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19 Jun 2018 Clock

A clock is started at noon. By 20 minutes past 4, the hour hand has turned through how many degrees?

OPtion

1) 90°
2) 120°
3) 130°
4) 125°
5) 105°
6) 110°
7) 115°
8) 100°
9) 135°
10) None of these

Solution

We know that angle traced by hour hand in 12 hrs = 360°
So angle traced in 1 hours = 360/12 = 30°

Time duration from noon to 20 minutes past 4 = 4 hours 20 minutes = 4 hour + 20/60 hours = 13/3 hours

Angle traced in 1 hours = 360/12 = 30°
Hence the angle traced by hour hand in 13/3 hours = 130°

Correct Option: 3 Best Solution (3)

MANDEEP KAUR   5 years AGO

in 1 hr the hour hand covers= 30
At 4:20= 30*4+20*(30/60)= 130 deg.

Like? Yes (3) | No (2)  

Sangeetha S   5 years AGO

Angle traced by hour hand in 12 hrs=360.
Angle traced by hour hand in4hrs 20 mins are (4+60)+20=13/3.
=(13/3)*(360/12)=130

Like? Yes | No (2)  

Vishnuvarthini K   5 years AGO

Angle traced by hour hand in 12 hrs=360 degrees
Angle traced by hour hand in 4 hrs 20 mins (13/3) hrs=(360/12)(13/3) = 130 degrees

Like? Yes | No (2)