Question:
In a class of 20 students, one student aged 18 years is replaced by a new student, and the average age of the class falls by 2 months. What is the age of the new student?
In a class of 20 students, one student aged 18 years is replaced by a new student, and the average age of the class falls by 2 months. What is the age of the new student?
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Introduce a variable for the original (unknown) average age and set up one equation connecting the old and new averages and totals.
Updated On: Jul 8, 2026
- 14 years
- 14 years 4 months
- 14 years 6 months
- 14 years 8 months
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The Correct Option is D
Solution and Explanation
The total age drops by \(20\times 2 = 40\) months \(= 3\) years 4 months. New student's age \(=\) old student's age \(-\) total drop \(= 18\text{ y} - 3\text{ y }4\text{ m} = 14\) years 8 months. Correct option: 14 years 8 months.
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