Find Arithmetic mean
Marks : less than 10,less than 20, less than 30, less than 40, less than 50
Students :5,17,31,41,49
Answers
Given:
Marks: < 10 < 20 < 30 < 40 < 50
Students: 5 17 31 41 49
To find:
The arithmetic mean for the following data
Calculation:
The data is given as per cumulative frequency distribution, so first convert it into simple frequency distribution
Marks Number of students
0-10 5
10-20 17-5 = 12
20-30 31-17 = 14
30-40 41-31 = 10
40-50 49-41 = 8
Now calculate the mean for the following simple frequency distribution
Marks Mid value(m) Frequency(f) f×m
0-10 5 5 25
10-20 15 12 180
20-30 25 14 350
30-40 35 10 350
40-50 45 8 360
∑f = 49 ∑fm = 1265
Arithmetic mean = ∑fm / ∑f = 1265/49
= 25.82
Final answer:
The arithmetic mean is 25.82 marks
Answer:
answer of this question is 28.6