Question
The average age of 26 children and their teacher's age
are 22 years. If the teacher's age is excluded, the average reduces by 1. What is the teacher's age?Solution
Sum of the age of total children and teacher = 27 × 22 = 594 Sum of the age of children after excluding = 26 × 21 = 546 Teacher’s age = 594 – 546 = 48 years
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