13. statistics — ગણિત ધોરણ 11 સાયન્સ — Question

$1,2,3,4,6,7$

Mean $=\frac{1+2+3+4+5+6+7}{7}=\frac{28}{7}=4$

Variance $=\sum_{+ r =1}^{ n } \frac{\left( x - x _{ i }\right)^2}{ n }=$

$\frac{(1-4)^2+(2-4)^2+(3-4)^2+(4-4)^2+(5-4)^2+(6-4)^2+(7-4)^2}{7}$

$=\frac{3^2+2^2+1^2+0+1^2+2^2+3^2}{7}$

$=\frac{9+4+1+1+4+9}{7}=\frac{28}{7}=4$

standard deviation $=\sqrt{\text { variance }}$

$\sqrt{4}=2$