Example 4: Time when clock hands are in opposite directions
Last Updated On: Sat Aug 29 2026Given Data
- Time interval: Between 7 o'clock and 8 o'clock.
- Target angle: 180 degrees.
Question
At what time between 7 and 8 o'clock will the hands of a clock be in a straight line pointing in opposite directions?
Answer
5 5/11 minutes past 7.
Solution
- Set up the formula: |30H - 5.5M| = 180.
- Substitute H = 7: |30(7) - 5.5M| = 180 => |210 - 5.5M| = 180.
- Solving 210 - 5.5M = 180 gives 5.5M = 30.
- M = 30 / 5.5 = 60 / 11 = 5 5/11 minutes.
- Therefore, the hands are opposite each other at 5 5/11 minutes past 7.