Question

The average age of a group of 8 persons was 14 years. A person with age 28 years left the group and a new person with age 16 years joined the group. Find the new average age of the group. *
​

Answer 1

Answer:

1. 13yrs

2. 14yrs

3. 15.5yrs

4. 12.5yrs

Answer 2

The new average age of the group is 12.5 Years if The average age of a group of 8 persons was 14 years A person with age 28 years left the group and a new person with age 16 years joined the group

Given:

• The average age of a group of 8 persons was 14 years
• A person with age 28 years left the group
• A new person with age 16 years joined the group

To Find:

• The new average age of the group

Solution:

• $\text{Mean}=\dfrac{\text{sum of all the obervations}}{\text{number of the observations}}$

Step 1:

Find Total age of the group

Number of Persons x Average Age

8 x 14 = 112  years

Step 2:

One person left and one person joined hence total persons are same as earlier 8

Step 3:

Find New Total age

112 - 28  + 16

= 100 Years

Step 4:

Find New Average age

100/8

= 12.5 Years

Hence , The new average age of the group is 12.5 Years