Question

there are 20 boys 10 girls in class 10 in a school the mean of 20 boys is 35 and 10 girls is 40 find the mean of total class ​

Answer 1

Your Answer :

Given:

No. of boys = 20

No. of girls = 10

Mean of 20 boys = 35

Mean of 10 girls = 40

Required to find:

1. Mean of the total class

Solution:

In the question it is given that there are 20 boys and 10 girls in class 10 of the school .

So, we have to find the Total no. of students

Hence,

Total no. of students = No. of boys + No. of girls

= 20 + 10

= 30

However they gave us some that is

Mean of 20 boys is 35

similarly, Mean of 10 girls is 40

Hence ,

We have to find the sum of their means respective.

Mean = sum of the observations / No. of observations

sum of the observations = Mean × No. of observations.

So,

The sum of the boys is

= 35 × 20

= 700

similarly,

The sum of the girls is

= 40 x 10

= 400

Now , add the respective sums of boys and girls

That is

700 + 400 = 1100

Hence,

the mean of the total class is

Mean = Sum of the boys and girls / Total no. of students

so, Mean of total class = 1100 / 30

= 36.666--------

= 36.7 ( approximately)

Therefore

Mean of the total class is 36.7