ðɪ ɚɹˈɪθmətˌɪk mˈiːn əvə sˈɛt ʌv əbzˈɜːvd dˈeɪɾə ɪz ˈiːkwəl tə ðə sˈʌm ʌvðə nuːmˈɛɹɪkəl vˈæljuːz ʌv ˈiːtʃ ɑːbzɚvˈeɪʃən, dᵻvˈaɪdᵻd baɪ ðə tˈoʊɾəl nˈʌmbɚɹ ʌv ɑːbzɚvˈeɪʃənz.
The arithmetic mean of a set of observed data is equal to the sum of the numerical values of each observation, divided by the total number of observations.