Question

2). Determine the value of mode from the following frequency distribution :
X : 0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80
F : 4 12 18 25 16 9 7 3​

Answer 1

Answer:

Class intervals Frequency

10-20 7

20-30 12

30-40 20

40-50 11

50-60 8

Here maximum frequency is 20 ,the class corresponding to this 30-40

So modal class is 30-40

Now lower limit of modal class (l)=30

Frequency (f1) of modal class =20

frequency (f0) of preceding the modal class =12

frequency (f2) of the class succeeding the modal class=11

Class size=10

Mod=l+[

2f1−f0−f2

f1−f0

]×h

Mod =30+[

2×20−12−11

20−12

]×10=30+

17

8

×10=30+4.705=34.705