Question

the table below shows the marks obtained in mathematics 100 find the mean marks obtained by the students by a suitable method
marks 0-10 10-20 20-30 30-40 40-50
no of students 20 10 20 30 20

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Answer 1

Answer:

27

Step-by-step explanation:

To find mean marks;

first, find class marks,i.e; x.

0-10 = (0+10)/2 = 5

10-20 = (10+20)/2 = 15

20-30 = (20+30)/2 = 25

30-40 = (30+40) /2 = 35

40-50 = (40+50)/2 = 45

Now, we need to find f and fx (total)

f = 20+10+20+30+20 = 100

fx= 20*5+10*15+20*25+30*35+20*45

= 100+150+500+1050+900

=2700.

Now, Mean = 2700/100 = 27