Question

if median of frequency distribution is 46 find missing frequency
cI. 10-20;20-30;30-40;40-50;50-60;60-70;70-80
frequency
12 ,30,x,65,y,25,18. total fi is 229

Answer 1

☺☺ HERE IS YOUR ANSWER ☺☺

150 + x + Y = 229
x + Y = 79


Median (M) = 46
Total frequency = 229
f = 65
cf = 42 + x
L = 40
C = 10
n/2 = 229/2

Median(M) = l + (n/2 - cf)/f × C

46 = 40 + (229/2 - 42 - x ) 65× 10

(46-40) × 65 = (229 - 84 - 2x)/2 × 10

390/10 =( 145 -2x)/2

39 × 2 = 145 - 2x

78 - 145 = -2x

-67 = -2x

x = 33.5


put value of x in eq (1).

33.5 + Y = 79

Y =45.5

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THANKS ........

Answer 2

Median=46

X+Y+150=229

X+Y=79

N/2=229/2=114.5

Median= l+[N/2-cf/f]h

46=40+[229/2-42-X/65]10

46-40=[114.5-42-X/13]2

6=[114.5-42-X/13]2

6*13/2 (72.5-X)

39=72.5-X

39-72.5=X

33.5=X

X+Y+150=229

33.5+Y+150=229

Y=229-183.5

=42.5

Therefore, X=33.5 and Y=42.5

Hope it helps u.......