The lifespan of zebras in a particular zoo are normally distributed. the average zebra lives 20.5 years the standard deviation is 3.9 years.

use the empirical rule (68-95-99.7%) to estimate the probability of a zebra living less than 32.2 years.

68% of the zebras have lifespan between 16.6 and 24.4 years.

Step-by-step explanation:

We are given the following information in the question:

Mean, μ = 20.5 years

Standard Deviation,  σ =  3.9 years

Empirical Formula:

Almost all the data lies within three standard deviations of the mean for a normally distributed data.

About 68% of data lies within one standard deviation of mean

About 95% of data lies within two standard deviation of the mean.

About 99.7% of data lies within three standard deviation of the mean.

We have to find the percentage of Zebras having lifespan between 16.6 and 24.4 years.

We can write:

16.6=20.5-3.9=μ-σ

24.4=20.5+3.9=μ+σ

Thus, by empirical rule around 68% of data lies within one standard deviation from the mean.

Thus, 68% of the zebras have lifespan between 16.6 and 24.4 years.