N - Questions find the median of the follow ing marks less than 10 less than 20....less than 70 /no of students 15 _35_60_84_6_120_125
Answers
Answer:
HEY THIS IS YOUR ANSWER!!!
Step-by-step explanation:
(i)
Class interval Frequency Cumulative frequency
0−10 0 0
10−30 10 10
30−50 15 25
50−70 18 43
70−90 22 65
90−110 22 87
110−130 9 96
130−150 4 100
N=100
We have, N=100,
2
N
=50
The cumulative frequency just greater than
2
N
is 65 then median class is 70−90 such that,
l=70,h=90−70=20,f=22,cf=43
Median=l+
f
2
N
−cf
×h
⇒ Median=70+
22
50−43
×20
⇒ Median=70+
22
7×20
⇒ Median=70+6.36
∴ Median=76.36
(ii)
Class interval Frequency Cumulative Frequency
80−90 9 9
90−100 17 26
100−110 19 45
110−120 45 90
120−130 33 123
130−140 15 138
140−150 12 150
150−160 0 150
N=150
We have, N=150, then,
2
N
=
2
150
=75
The cumulative frequency just more than
2
N
is 90 then the median class is 110−120 such that
l=70,h=120−110=10,f=45,
⇒ Median=110+ 45 /75−45 ×10
⇒ Median=110+ 30×10/45
⇒ Median=110+6.67
∴ Median=116.67