In: Statistics and Probability
In a certain state,
37.637.6%
of all community college students belong to ethnic minorities. Find the probabilities of the following results in a random sample of
1010
of the community college students.a. Exactly
33
belong to an ethnic minority.
b. Three or fewer belong to an ethnic minority.
c. Exactly
66
do not belong to an ethnic minority.d.
SixSix
or more do not belong to an ethnic minority.
a.
P(33)equals=nothing
(Round to four decimal places as needed.)
b. P(three or fewer belong to an ethnic
minority)equals=nothing
(Round to four decimal places as needed.)
c. P(exactly
66
do not belong to an ethnic
minority)equals=nothing
(Round to four decimal places as needed.)
d.
P(sixsix
or more do not belong to an ethnic
minority)equals=nothing
(Round to four decimal places as needed.)
p = 0.376
n = 10
P(X = x) = 10Cx * 0.376x * (1 - 0.376)10-x
a) P(X = 3) = 10C3 * 0.3763 * (1 - 0.376)7 = 0.2350
b) P(X < 3) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3)
= 10C0 * 0.3760 * (1 - 0.376)10 + 10C1 * 0.3761 * (1 - 0.376)9 + 10C2 * 0.3762 * (1 - 0.376)8 + 10C3 * 0.3763 * (1 - 0.376)7
= 0.4441
c) p = 1 - 0.376 = 0.624
P(X = 6) = 10C6 * 0.6246 * (1 - 0.624)4 = 0.2478
d) P(X > 6) = P(X = 6) + P(X = 7) + P(X = 8) + P(X = 9) + P(X = 10)
= 10C6 * 0.6246 * (1 - 0.624)4 + 10C7 * 0.6247 * (1 - 0.624)3 + 10C8 * 0.6248 * (1 - 0.624)2 + 10C9 * 0.6249 * (1 - 0.624)1 + 10C10 * 0.62410 * (1 - 0.624)0
= 0.6919