Question

Prepare a frequency table using a class interval 100-199 and obtain the arithmetic mean. Pls answer the question in English​

Answer 1

Answer:

Answer

Class

Interval Frequency

(f) Cumulative frequency (cf)

10−20 12 12

20−30 30 12+30=42

30−40 a 42+a=42+a

40−50 65 42+a+65=107+a

50−60 b 107+a+b=107+a+b

60−70 25 107+a+b+25=132+a+b

70−80 18 132+a+b+18=150+a+b

Here n=230

150+a+b=230

∴a+b=80

As n=230,

2

n

=115

This observation lies in the class 40-50.

So, the median class is 40-50.

∴l=40,

2

n

=115,cf=42+a,f=65 and c=10.