 <translate> Explanation: Sum of the ages of the students = 39×15 = 585
New average = 15 years 3 months = 15 + 1414 year
Sum of the ages of students and teacher = 40×15141514 = 40×614614 = 610
Teacher age = 610 – 585 = 25 years. <yor> Àlàyé: Àpapọ̀ ọjọ́ orí àwọn akẹ́kọ̀ọ́ = 39 × 15 = 585 Apapọ tuntun = ọdún mẹ́ẹ̀ẹ́dógún oṣù mẹ́ta = ọdún mẹ́ẹ̀ẹ́dógún + 1414 Àpapọ̀ ọjọ́ orí àwọn akẹ́kọ̀ọ́ àti olùkọ́ = 40×15141514 = 40×614614 = 610 Ọjọ́ orí olùkọ́ = 610 <unk> 585 = 25 ọdún. 