Q. In the data set below, what is the variance?9,4,9,4,6,1If the answer is a decimal, round it to the nearest tenth.variance (σ2): _____
Calculate squared differences: Now, calculate the squared differences from the mean for each data point.(9−5.5)2+(4−5.5)2+(9−5.5)2+(4−5.5)2+(6−5.5)2+(1−5.5)2= (3.5)2+(−1.5)2+(3.5)2+(−1.5)2+(0.5)2+(−4.5)2= 12.25+2.25+12.25+2.25+0.25+20.25= 49.5
Find the variance: Finally, divide the sum of squared differences by the number of data points to find the variance.σ2=NΣ(xi−μ)2σ2=649.5σ2=8.25Since we need to round to the nearest tenth, σ2≈8.3
More problems from Variance and standard deviation