Question

if the mean of observations x1,x2,......,.....,x10 is 20. find the mean of x1+4,X2+8,x2+8,X3+12,....,....,x10+ 40

Answer 1

1x+2x+3x+4x+5x+6x+7x+8x+9x+10x
___________________________. =20
10
55x=200
x=200/55
x=40/11

therefore mean of observations 1x+4,2x+8,.....,10x+40 is 384