The Exponential Distribution (Optional) · Exercise 29

The percent of persons (ages five and older) in each state who speak a language at home other than English is approximately exponentially distributed with a mean of 9.848. Suppose we randomly pick a state.

(a) Define the random variable. X = _________________________________.
(b) Is X continuous or discrete?
(c) X ~ ________
(d) μ = ________
(e) σ = ________
(f) Draw a graph of the probability distribution. Label the axes.
(g) Find the probability that percentage is less than 12.
(h) Find the probability that percentage is between eight and 14.
(i) The percent of all individuals living in the United States who speak a language at home other than English is 13.8.
(a) Why is this number different from 9.848 percent?
(b) What would make this number higher than 9.848 percent?

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Statistics · §5.3 The Exponential Distribution (Optional) · Exercise 29