Question

there are two sections in IX class. the mean of the marks secured by 30 students of section a is 45, that of 50 students of sectiom b is 54. find the mean of all marks of students of the class

Answer 1

Answer:

Mean of all marks secured by students of both sections is 48.21

Step-by-step explanation:

Mean = (Sum of observations) /(total number of observations)

In section A,

Mean= (Sum of observations) /30=45

→ Sum of observations= 45×30

→ Sum of observations= 1350

In section B,

Mean= (Sum of observations)/50=54

→ Sum of observations= 54×50

→ Sum of observations= 2700

Mean of total marks= (Total sum of observations)/(Total number of observations)= (1350+2700)/(30+54)

= 4050/84

= 48.21

Thus, the mean of all marks secured by students of both sections is 48.21