Question

A school has 4 section of Chemistry in Class X having 40,
35,45 and 42 students. The mean marks obtained in Chemistry
test are 50, 60, 55 and 45 respectively for the 4 sections.
Determine the overall average of marks per student
(a) 5025
(b) 5225
(c) 51.25
(d) 53.25​

Answer 1

Answer:

For getting overall average we need to find out the total marks got accross all the sections and then if we devide it by the total number of students,we can easily get the average

So average = (40×50+35×60+45×55+42×45)/(40+35+45+42)

=52.25

option b is correct

Thanks you