Where will the hour hand of a clock stop if it starts
from 10 and turns through 3 right angles ?

Answer

To solve the problem of where the hour hand of a clock will stop if it starts from 10 and turns through 3 right angles, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Movement of the Hour Hand**:
- The hour hand of a clock moves in a circular manner. A full circle (360 degrees) represents 12 hours.

2. **Determine the Value of a Right Angle**:
- A right angle is 90 degrees. Therefore, 3 right angles equal:
\[ 3 \times 90^\circ = 270^\circ \]

3. **Calculate the Hour Hand Movement**:
- The hour hand moves 360 degrees in 12 hours, which means it moves:
\[ \frac{360^\circ}{12 \text{ hours}} = 30^\circ \text{ per hour} \]
- To find out how many hours correspond to a 270-degree movement, we can calculate:
\[ \text{Hours} = \frac{270^\circ}{30^\circ \text{ per hour}} = 9 \text{ hours} \]

4. **Determine the New Position of the Hour Hand**:
- Starting from 10, we need to move the hour hand 9 hours forward. We can count the hours on the clock:
- From 10 to 11 (1 hour)
- From 11 to 12 (2 hours)
- From 12 to 1 (3 hours)
- From 1 to 2 (4 hours)
- From 2 to 3 (5 hours)
- From 3 to 4 (6 hours)
- From 4 to 5 (7 hours)
- From 5 to 6 (8 hours)
- From 6 to 7 (9 hours)

5. **Final Position**:
- After moving 9 hours forward from 10, the hour hand will stop at 7.

### Final Answer:
The hour hand will stop at **7**.

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