Question 1149930: Marks of 75 students are summarized in the following frequency distribution:
marks Number of students
40-44 7
45-49 10
50-54 22
55-59 f4
60-64 f5
65-69 6
70-74 3
If 20% of the students have marks between 55 and 59. Find the missing frequencies, mean, median and mode.
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! 20% of 75 is 15, so for 55-59 or f4, the number is 15
then 60-64 has to be 12
7
10
22
15
12
6
3
the distribution
the mode is 52 (midway between 50-54), the most of all the groups.
median is between the 37th and 38th observation or 52, the middle of the 50-54 range
mean is numerator of 7*42+10*47+22*52+15*57+12*62+6*67+3*72 divided by 75, and that is 55.
|
|
|
