kfind out mode from the following data x 0-50 50-100 100-150 150-200 200-250 250-300 300-350 f 47,171287, 497382, 211,87 solve
Answers
Answer:
Class interval Mid value
x
i
Frequency
f
i
f
i
x
i
cf
0−50 35 2 50 2
50−100 75 3 225 5
100−150 125 5 625 10
150−200 175 6 1050 16
200−250 225 5 1127 21
250−300 275 3 825 24
300−350 325 1 325 25
∑f
i
=25 ∑f
i
x
i
=4225
⇒ Mean=
∑f
i
∑f
i
x
i
=
25
4225
=169
⇒ We have N=25$. Then,
2
N
=12.5
⇒ So, median class is 150−200.
l= lower limit of the modal class
h= size of the class intervals
f= frequency of the modal class
f
1
= frequency of the class preceding the modal class
f
2
= frequency of the class succeed in the modal class.
∴ l=150,h=200−150=50,f=6,cf=10
⇒ Median=l+
f
2
N
−cf
×h
⇒ Median=150+
6
12.5−10
×50
⇒ Median=150+
6
125
∴ Median=150+20.83=170.83.
⇒ Here maximum frequency is 6, then the corresponding class 150−200 is the modal class.
⇒ l=150,h=50,f=6,f
1
=5f
2
=5
⇒ Mode=l+
2f−f
1
−f
2
f−f
1
×h
⇒ Mode=150+
2×6−5−5
6−5
×50
⇒ Mode=150+
2
50
∴ Mode=150+25=175