Which of these two sets of scores has a higher standard deviation? 10x Reviewers rating of movies out of ten: INCEPTION 10 9 9 10 9 10 9 8 10 8 SCOTT PILGRIM SAVES THE WORLD 10 1 3 10 2 7 10 4 10 10
+529 INCEPTION 10 9 9 10 9 10 9 8 10 8
mean μ = 92÷10 = 9.2
σ2 = ( 4*(10-9.2)2 + 4*(9-9.2)2 + 2*(8-9.2)2 )÷10
= 0.56
⇔ standard deviation for this data set, σ = 0.748
SAVES THE WORLD 10 1 3 10 2 7 10 4 10 10
mean μ = 67÷10 = 6.7
σ2 = ( 4*(10-6.7)2 + (7-6.7)2 + (4-6.7)2 + (3-6.7)2 + (2-6.7)2 + (1-6.7)2 )÷10
= ......
⇔ standard deviation for this data set, σ = ....
I leave the remaining calculator work as an exercise for the student. 
+529 INCEPTION 10 9 9 10 9 10 9 8 10 8
mean μ = 92÷10 = 9.2
σ2 = ( 4*(10-9.2)2 + 4*(9-9.2)2 + 2*(8-9.2)2 )÷10
= 0.56
⇔ standard deviation for this data set, σ = 0.748
SAVES THE WORLD 10 1 3 10 2 7 10 4 10 10
mean μ = 67÷10 = 6.7
σ2 = ( 4*(10-6.7)2 + (7-6.7)2 + (4-6.7)2 + (3-6.7)2 + (2-6.7)2 + (1-6.7)2 )÷10
= ......
⇔ standard deviation for this data set, σ = ....
I leave the remaining calculator work as an exercise for the student.
