40. What is the angle between the minute hand and hour hand when the clock shows 4:25 hours?
- A. 12.5°
- B. 15°
- C. 17.5°
- D. 20°
Answer: C
Explanation
To find the angle between the minute hand and hour hand, we can use the formula: Angle = |30H – (11/2)M|, where H is the hour and M is the minutes. Here, H = 4 and M = 25. Angle = |30 × 4 – (11/2) × 25| = |120 – (275/2)| = |120 – 137.5| = |-17.5| = 17.5°. Alternatively, we can calculate the position of each hand from the 12 o’clock mark. The minute hand moves 6° per minute, so at 25 minutes, it is at 25 × 6° = 150°. The hour hand moves 30° per hour and 0.5° per minute. At 4:25, its position is 4 × 30° + 25 × 0.5° = 120° + 12.5° = 132.5°. The angle between the hands is the absolute difference: |150° – 132.5°| = 17.5°. This question tests knowledge of clock problems and angle calculations.