**The average temperature for the first four days of a week is 40.2°C and that of the last four days is 41.3°C. If the average temperature for the whole week is 40.6°C, then the temperature on the fourth day is?**

### Note

**The temperature on the fourth day**

**= [{(40.2 × 4) + (41.3 × 4)} - (40.6 × 7)]°C**

**= 41.8°C.**