Question
The average age of 28 children and their teacher's age
are 24 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 = 29 × 24 = 696 Sum of the age of children after excluding = 28 × 23 = 644 Teacher’s age = 696 – 644 = 52 years
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