Average is the sum of all the data divided by amount of data you have (for example, the average of the data set {5,8,12} is the sum, 25, divided by the amount of data, 3).
So, since Deepak has played six games and has lost 1,004 points total (the sum of all six games), the average number of points he lost is 1004/6.
The average number of points lost each game is 167.33