If in a class of 20 students, 5 students have scored 76 marks, 7 students have scored 77 marks and 8 students have scored 78 marks, then compute the mean of the class.
GIVEN: total no of students = 20
5 students have scored 76 marks
7 students have scored 77 marks
8 students have scored 78 marks
FORMULA USED: Arithmetic mean =
Number of students = 20
Sum of marks = (5×76) + (7×77) + (8×78)
= 380 + 539 + 624
= 1543
Arithmetic mean =
Arithmetic mean = = 77.15
CONCLUSION: Arithmetic Mean of marks of class is 77.15