A walks 10 metres in front and 10 metres to the right. Then every time turning to his left, he walks 5, 15 and 15 metres respectively. How far is the now from his starting point ?

Explanation

To solve the problem step by step, we will track A's movements and calculate the distance from the starting point to the final position.

### Step-by-Step Solution:

1. **Starting Point**: Let's assume A starts at point O (0, 0) on a coordinate plane.

2. **First Move**: A walks 10 meters in front (north).
- New position: O (0, 0) to A (0, 10).

3. **Second Move**: A turns to the right (east) and walks 10 meters.
- New position: A (0, 10) to B (10, 10).

4. **Third Move**: A turns left (now facing north) and walks 5 meters.
- New position: B (10, 10) to C (10, 15).

5. **Fourth Move**: A turns left (now facing west) and walks 15 meters.
- New position: C (10, 15) to D (−5, 15).

6. **Fifth Move**: A turns left (now facing south) and walks 15 meters.
- New position: D (−5, 15) to E (−5, 0).

7. **Final Position**: A's final position is at point E (−5, 0).

8. **Distance Calculation**: To find the distance from the starting point O (0, 0) to the final position E (−5, 0), we can use the distance formula:
\[ \text{Distance} = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} \]
Substituting the coordinates:
\[ \text{Distance} = \sqrt{(-5 - 0)^2 + (0 - 0)^2} = \sqrt{(-5)^2} = \sqrt{25} = 5 \text{ meters} \]

### Final Answer:
A is now 5 meters away from his starting point.

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