Question

The mean age of a family of 6 members is 25
years. The mean age of the family after a 45
year old member leaves is
a) 19 years (b) 21 years
e) 23 veurs (d) 25 years​

Answer 1

Let the sum of ages of 6 members be x

x/6=25

x=25*6

x=150

Now when a 45 years old member left then the sum of ages of 5 members will be x-45

Noe new mean is:

x-45/5

150-45/5

105/5

21

therfore new mean is 21 years (option b)

Answer 2

Answer:

(b)

explanation:

Let , total sum of ages of all members be "x".

Mean = 25

X/6 =25

X=25×6

X= 150

In the total age , a 45 year old member leaves

Then total age =150-45

= 105

Total members=6-1=5

$mean = \frac{105}{5} \\ = 21 \: years$

Therefore, (b) 21 years is the answer.