Variance = summation of (x - mean)^2 all divided by the number of dataset.
mean = (17 + 5 + 11 + 1 + 11)/5 = 9
Variance = [(17 - 9)^2 + (5 - 9)^2 + (11 - 9)^2 + (1 - 9)^2 + (11 - 9)^2]/5 = (8^2 + (-4)^2 + 2^2 + (-8)^2 + 2^2}/5 = (64 + 16 + 4 + 64 + 4)/5 = 152/5 = 30.4
The final answer to tour problem 16.3
The formula for circumference is
C=(pi)d
11304=(pi)d
assume pi is 3.14
rearrange formula
d= c / (pi)
= 11304 / 3.14
d= 3600
262.5 miles
explanation 1/4 is half of 1/2 so 52.5 is half of 105 and then 210 for an hour of travel