Question

у- CI+4x ) ( 34 х - e) 2​

Answer 1

Step-by-step explanation:

Classes Frequency c.f

0−10 5 5

10−20 x 5+x

20−30 6 11+x

30−40 y 11+x+y

40−50 6 17+x+y

50−60 5 22+x+y

Total 40

⇒ 22+x+y=40

∴ x+y=18 ----- ( 1 )

⇒ Here, median class =30−40

⇒ l=30,c.f=11+x,f=y,h=10,

2

n

=

2

40

=20

⇒ Median =31

Median=l+

⎣

⎢

⎡

f

2

n

−cf

⎦

⎥

⎤

×h

31=30+[

y

20−(11+x)

]×10

1=

y

9−x

×10

∴ 10x+y=90 ---- ( 2 )

Now, subtracting equation ( 1 ) from ( 2 ), we get

x=8 and

y=10