We need to find where will the hour hand of a clock stop for the given set of questions Consider clock to be 360° and the clock marks up to 12 360/12 = 30 degrees per hour (a) From 6 and turns through 1 right angle? 6 o’ clock = 6 X 30 = 180 ° From 180, a turn of right angle 180+90/ 30= 270/30= 9 So the hour hand would be at 9 (b) If the hour hand of a clock starts from 8 and turns through 2 right angle 8 o’clock = 8* 30° = 240° 240+2*90= 240+180= 420° 420/30= 14 We know that as per 24-hour format 14:oo hours stands for 2 o’clock So, the hour hand would be at 2 o’clock (c) If the hour hand of a clock starts from 10 and turns through 3 right angle 10 o’clock = 10* 30° = 300° 300+ 3*90 = 570/30 = 19 We know that as per 24-hour format 19:oo hours stands for 7 o’clock So, the hour hand would be at 7 o’clock (d) If the hour hand of a clock starts from 7 and turns through 2 straight angles, then it will stop at 7 7 o’ clock = 7* 30 = 210 ° 210+ 2 * 180 = 210+360 = 570/30= 19 We know that as per 24-hour format 19:oo hours stands for 7 o’clock So, the hour hand would be at 7 o’clock
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