At 9:42 A.M., through how many degrees has the hour hand of a clock moved since noon the previous day?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 651
The hour hand goes round the dial once (360°) in 12 hours, so it turns 30° every hour, that is 0.5° every minute. The angle it has turned depends only on the time that has passed.
Noon to midnight: 12 h; midnight to 9:42 a.m.: 9 h 42 min
Time passed: 21 h 42 min \(=21\times60+42=1302\) minutes
Angle turned \(=1302\times0.5=\) 651°