Question

class interval-0-7,7-14,14-21,21-28,28-35,35-42,42-49 frequency-3,4,7,11,0,16,9 cumulative frequency-3,7,14,25,25,41,50 median calass ? which cumulative frequency we should choose 25 or 41?​

Answer 1

Answer:

Answer

Marks No of students fi cf

0−7 3 3

7−14 4 7

14−21 7 14

21−28 11 25

28−35 0 25

35−42 16 41

42−49 9 50

Sum =50

Where cf= cumulative frequency

Median =L+

⎩

⎪

⎪

⎪

⎨

⎪

⎪

⎪

⎧

h×

f

(

2

N

−cf)

⎭

⎪

⎪

⎪

⎬

⎪

⎪

⎪

⎫

Here:

N=50

N/2=25

Here cumulative frequency is 25

Median class =21−28

So, L=21, h=7, f=11 and

cf=cf of preceding class i.e 14

Substitute all the value in the above formula, we get

Median =21+{7×(25−14)/11}

=28