Let x be a binomial random variable with n
20 and p .1.
a. Calculate P(x 4) using the binomial formula.
b. Calculate P(x 4) using Table 1 in Appendix I.
c. Use the Excel output below to calculate P(x 4).
Compare the results of parts a, b, and c.
d. Calculate the mean and standard deviation of the
random variable x.
e. Use the results of part d to calculate the intervals
m s, m 2s, and m 3s. Find the probability
that an observation will fall into each of these
intervals.
f. Are the results of part e consistent with Tchebysheff’s Theorem? With the Empirical Rule? Why
or why not?