The average age of 30 boys of a class is equal to 14 years. When the age of the class teacher is included the average becomes 15 years. Find the age of the class teacher? A.50 B.44 C.45 D.42 E.None of these

1 Answer

Answer :

Answer – C (45)

Explanation – Total ages of 30 boys = 14 x 30 = 420 years

Total age when class teacher is included = 15 x 31 = 465 years

Age of class teacher = 465 – 420 = 45 years

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