 <translate> Give the step-by-step reasoning process and then the final answer. Colin ran his first mile in 6 minutes. He ran his next two miles in 5 minutes each and finished his 4th mile in 4 minutes. What was the average time it took him to run a mile? <yor> Ṣàlàyé bí wọ́n ṣe ń ronú lẹ́ẹ̀kan-lẹ́ẹ̀kan, kó o sì wá sọ ìdáhùn tó o máa fún wọn. Colin sáré kìlómítà kan láàárín ìṣẹ́jú mẹ́fà. Ó fi ìṣẹ́jú márùn-ún sáré kìlómítà méjì tó tẹ̀ lé e, ó sì fi ìṣẹ́jú mẹ́rin sáré kìlómítà kẹrin. Báwo ni iye àkókò tí wọ́n fi ń sáré kìlómítà kan ṣe pọ̀ tó? 