Find the mean and mode for the following data classes 10-20 20-30 30-40 40-50 50-60 60-70 70-80 frequency 4 8 10 12 10 42
Answers
Answer:
data classes fi xi fi * xi
10 -- 20 4 (10 + 20 ) / 2 = 15 60
20 -- 30 8 (20 + 30 ) / 2 = 15 200
30 -- 40 10 (30 + 40 ) / 2 = 15 350
40 -- 50 12 (40 + 50 ) / 2 = 15 540
50 -- 60 10 (50 + 60 ) / 2 = 15 550
60 -- 70 4 (60 + 70 ) / 2 = 15 260
70 -- 80 2 (70 + 80 ) / 2 = 15 150
50 2110
mean = summation of ( fi * xi ) / summation of fi
= 2110 / 50
= 42 . 20
mode = number that holds highest frequency
here, mode = 40 -- 50