1. **State the problem:** Mr Manu travelled 720 km in 8 hours. We need to find his speed in meters per second (m/s). 2. **Convert distance to meters:** Since 1 km = 1000 m, the distance in meters is $$720 \times 1000 = 720000\text{ m}$$. 3. **Convert time to seconds:** Since 1 hour = 3600 seconds, the time in seconds is $$8 \times 3600 = 28800\text{ s}$$. 4. **Calculate speed:** Speed is distance divided by time, so $$\text{speed} = \frac{720000}{28800} = 25\text{ m/s}$$. **Final answer:** Mr Manu's speed is **25 m/s**.