The lifespans of zebras in a particular zoo are normally distributed. The average zebra lives 20.5 point, 5 years; the standard deviation is
3.9
3.93, point, 9 years.
Use the empirical rule
(
68
−
95
−
99.7
%
)
(68−95−99.7%)left parenthesis, 68, minus, 95, minus, 99, point, 7, percent, right parenthesis to estimate the probability of a zebra living less than
32.2
32.232, point, 2 years.