Question

There there there are 40 students In a class out of them 15 or boys the mean of marks obtained by boys is 33 and that for girl is 35 find out mean of all students in the class ​

Answer 1

Answer:

Step-by-step explanation:

Given:-

Total no.of students = 40

Total no.of boys = 15

Total no. of girls = 40-15 = 25

Mean marks of boys = 33

Mean mark of girls = 35

To find:-

Mean of all students

Solution:-

Let's assume,

Sum of marks of boys = x

Sum of marks of girls = y

Therefore,

x/Total boys = 33 (mean)

x/15 = 33

× = 33 × 15

x = 495

y/Total girls = 35 (mean)

y/25 = 35

y = 25 × 35

y = 875

=> Total marks by all = x + y

=> Total marks by all = 495 + 875

=> Total marks by all = 1370

Therefore,

Mean of all students = Total mark/Total students

Mean of all students = 1370/40

Mean of all students = 137/4

Mean of all students = 34.25