Answer:
0.172 ; 0.0884 ; 0.9115
Step-by-step explanation:
Proportion or those who feel secure, p = 0.45
Sample size, n = 8
Using the binomial distribution formula :
P(x =x) = nCx * p^x * (1 - p)^(n - x)
A.) p(x = 5)
P(x =5) = 8C5 * 0.45^5 * 0.55^3
P(x = 5) = 56 * 0.0184528125 * 0.166375
P(x = 5) = 0.1719248540625
P(x = 5) = 0.172
B.) P(x > 5)
P(x > 5) = P(x = 6) + P(x = 7) + P(x = 8)
P(x > 5) = 0.0703 + 0.0164 + 0.0017
P(x > 5) = 0.0884
C.) P( ≤ 5) = P(x = 0) + P(x = 1) + P(x = 2) + P(x = 3) + P(x = 4) + P(x = 5)
Using the binomial probability calculator to obtain a direct solution :
P( ≤ 5) = 0.9115
345,000 ; 350,00 ; 300,000.
