Question 909170
88% ≤ 55,000
X the mean distance traveled per year
z = invNorm(.88) = (55,000 - X)/645
645invNorm(.88) = 55,000 - X
X =  55,000 - 645invNorm(.88)
X = 55,000 - 645(1.175) = 54,242.125, the mean distance traveled per year