Question

assume that the population consists of 7 containers having the following weight 6,7,8,9,10,11,12. Find mean μ and standard deviation.

Answer 1

$$mean=\mu=\dfrac{6+7+8+9+10+11+12}{7}=9$$

$$\sigma^2=\dfrac{1}{7}((6-9)^2+(7-9)^2+(8-9)^2$$

$$+(9-9)^2+(10-9)^2+(11-9)^2+(12-9)^2)$$

$$=4$$

$$\sigma=\sqrt{\sigma^2}=\sqrt{4}=2$$

Mean $\mu=9,$ standard deviation $\sigma=2.$