The average age of 20 students of a class is 12 years. Now a student whose age is 15 years leaves the class, and another student whose age is 13 years enters the class. Find the new average age of the class (in years).?

11.5
11.9
11.6
12.2
11.7

LohaHridoy

4 views

2025-01-04 04:42

1 Answers

AhmedNazir

Option 2 : 11.9

Given:

Average age of the class = 12 years

Total number of students in the class = 20

Age of the student leaving the class = 15 years

Age of the student entering the class = 13 years

Formula Used:

Total of ages of all the students = Average age of the class × Total number of students in the class

Calculation:

We obtain the new total age of the class as:

(12 × 20) - 15 + 13 = 238 years

So, the new average age of the class = 238/20 = 11.9 years

∴ The new average age of the class is 11.9 years

4 views Answered 2022-09-04 04:29

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