Q86.The mean age of 25 teachers in a school is 40 years. A teacher retires at the age of 60 years and a new teacher is appointed in his place. If the mean age of the teachers in this school now is 39 years, then the age (in years) of the newly appointed teacher is 5x8+7x6
What This Question Tests
This question tests the understanding of the definition of the mean and how it changes when one observation is removed and another is added, requiring a simple calculation of the sum of ages.
Concepts Tested
Formulas Used
Mean = (Sum of observations) / (Number of observations)
Sum = Mean × Number
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📋 Question Details
- Chapter
- Statistics
- Topic
- Mean of Data
- Year
- 2021
- Shift
- 18 Mar Shift 1
- Q Number
- Q86
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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