Determine whether the Los Angeles Angels or the Colorado Rockies had a relatively better run-producing season. The Angels scored 773 runs and play in the American League, where the mean number of runs scored was μ = 677.4 and the standard deviation was σ = 51.7 runs. The Rockies scored 755 runs and play in the National League, where the mean number of runs scored was μ= 640.0 and the standard deviation was σ = 55.9 runs.

Approach To determine which team had the relatively better run-producing season, compute each team’s z-score. The team with the higher z-score had the better season.
Because we know the values of the population parameters, compute the population z-score.