The arithmetic mean (sometimes called the "unweighted average" or "equally weighted average") can be interpreted as a special case of a weighted average in which all weights are equal to the same number ( in the above example and  in a situation with  numbers being averaged).
ðɪ ɚɹˈɪθmətˌɪk mˈiːn sˈʌmtaɪmz kˈɔːld ðə "ʌnwˈeɪɾᵻd ˈævɹɪdʒ" ɔːɹ "ˈiːkwəli wˈeɪɾᵻd ˈævɹɪdʒ"kæn biː ɪntˈɜːpɹɪɾᵻd æz ɐ spˈɛʃəl kˈeɪs əvə wˈeɪɾᵻd ˈævɹɪdʒ ɪnwˌɪtʃ ˈɔːl wˈeɪts ɑːɹ ˈiːkwəl tə ðə sˈeɪm nˈʌmbɚ ɪnðɪ əbˌʌv ɛɡzˈæmpəl ænd ɪn ɐ sˌɪtʃuːˈeɪʃən wɪð nˈʌmbɚz bˌiːɪŋ ˈævɹɪdʒd.