CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

For observations x1,x2,x3,..........,xn, if ni=1(xi+1)2=9n and ni=1(xi1)2=5n., then standard deviation of the data is
  1. 3
  2. 5
  3. 2
  4. 10


Solution

The correct option is B 5
Given that 
ni=1(xi+1)2=9n=ni=1(x2i+2xi+1)=9nx2i+2xi+n=9nx2i+2xi=8n........(1)ni=1(xi1)2=ni=1(x2i2xi+1)=5nx2i2xi+n=5nx2i2xi=4n........(2)(1)+(2)2x2i=12nx2i=6n(1)(2)4xi=4nxi=nσ=x2in(xin)2=61=5

flag
 Suggest corrections
thumbs-up
 
0 Upvotes


Similar questions
View More


People also searched for
View More



footer-image