. Find the variance of the observation values taken in the lab: $4.2,\ 4.3,\ 4.0,\ 4.1$.
🎥 Video solution / Text Solution of this question is given below:
Mean $,\bar x=\dfrac{4.2+4.3+4.0+4.1}{4}=4.15$.
Deviations: $0.05,,0.15,,-0.15,,-0.05$.
Sum of squares $=0.0025+0.0225+0.0225+0.0025=0.05$.
Population variance $,s^2=\dfrac{0.05}{4}=0.0125$.
Sample variance $,s^2=\dfrac{0.05}{3}\approx0.0167$.