Bowling average and strike rate means
The strike rate of a bowler is the average number of balls required by him to take 1 wicket. This can be worked out from the average and economy rates. For example, if a bowler has an average of 20 runs per wicket, and an economy rate of 4 runs per over, then to concede 20 runs he will require (20/4) = 5 overs = (5*6) = 30 balls.