2hrs and 18 mins = 138 mins
381 km / 138 mims = 2.76 km / minute
2.76 km / min * 60 = 165.6 km / hr
His two speeds for the whole journey include 165.6 km / hr and 30 km / hr.
165.6 + 30 = 195.6
195.6 / 2 = 97.8 km / hr
The average speed is 97.8 km / hr