TS EAMCET 5 May 2018 Shift 1 Solved Paper

The mean is expressed as,
mean=

sum of observation

n

40=

sum of weight

20

sum of weight =800
The variance is calculated as,
var=σ2
=25
The new mean is
calculated as,
New mean =

800−43−73

20−2

Xnew=38
Since, variance is 25 then,

∑x2

20

−(X)2=25

∑x2

20

−402=25
∑x2=32500
If two boys are removed then,
∑xnew2=32500−(43)2−(73)2
=25322
The new variance is calculated as,
σnew2=

∑xnew2

18

−(Xnew)2
=

25322

18

−(38)2
=26.78