Time duration when traveling at a speed of 40 km/h=\(\frac{200}{40}\)=5 hours
and time duration travelling at 20 km/h=\(\frac{200}{20}=10\) hours
Total time=\(10+5=15\space hours\)
So, Average Speed = \(\frac{400}{15}=26.67\space km/hr\)
The correct option is (C): 26.67 km/h