Question
The average age of 27 children and their teacher's age
are 23 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 = 28 × 23 = 644 Sum of the age of children after excluding = 27 × 22 = 594 Teacher’s age = 644 – 594 = 50 years
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