If ∑_(i=1)^9▒〖(x_i-5)=9〗 and ∑_(i=1)^9▒(x_i-5) ^2=45, then the standard deviation of the 9 termx_1,x_2,…,x_9s is
(a) 3 (b) 9 (c) 4 (d) 2
Ans: d
Sol.
The standard deviation is independent of change of origin. So, put x_i-5=y_i
∴∑_(i=1)^9▒〖y_i=9〗 and ∑_(i=1)^9▒〖y_i^2=45〗
S.D. =√(1/n ∑▒〖y_i^2-((∑▒y_i )/n)^2 〗)
=√(45/9-(9/9)^2 )=√(5-1)=√4=2
------------
If ∑_(i=1)^9 (x_i-5)=9 & ∑_(i=1)^9 (x_i-5) ^2=45 then standard deviation of the 9 term x_1 x_2 … x_9
Downloads our APP for FREE Study Material ,Video Class ,Test paper & Mock test etc...
Click to Download Impetus Gurukul Free Learning App here
https://play.google.com/store/apps/de...
To buy complete Course please Visit–
https://www.impetusgurukul.com or contact on 7047832474
join Impetus Gurukul live classes via the official Website:
https://live.impetusgurukul.com
Our Social links
Telegram: https://t.me/impetusgurukul
Facebook: / impetusgurukul
LinkedIn: / dr-sharad. .
twitter: / impetussharad