Question

The ages of the members of a club is given in the following

age(years) no of members
20 – 30 2
30 - 40 4
40 – 50 8
50 – 60 12
60 – 70 7
70 – 80 3
80 - 90 2
Calculate the mean age of the members of the club.

Answer 1

Step-by-step explanation:

You can solve this with the help of the table.

You can find the table in the textbook.

That table will help you a lot than any other.

Answer 2

Answer:

Solution :

First we have to construct a table for the given data. Please refer to video for creating complete table.

From the table,

∑fiui=25

∑fiu2i=705

N=∑fi=500 ∴ Variance (σ2)=[∑fiu2iN−(∑fiuiN)2]h2

Here, h= Class size =10

∴σ2=[705500−(25500)2]⋅102=102(1.4075)

∴ Standard deviation (σ)=102(1.4075)−−−−−−−−−√=10∗1.186=11.86

Now, Mean(X¯¯¯)=A+h[∑fiuiN]

Here, A= Assumed Mean =55

∴X¯¯¯=55+10(25500)=55.5

∴ Mean is 55.5.

Step-by-step explanation:

hope it helps u