Seventy percent of households say they would feel secure if they had $50,000 in
ID: 3151427 • Letter: S
Question
Seventy percent of households say they would feel secure if they had $50,000 in savings. You randomly select 8 households and ask them if they would feel secure if they had $50,000 in savings. Find the probability that the number that say they would feel secure is exactly five, more than five, and at most five Find the probability that the number that say they would feel secure is exactly five (Round to three decimal places as needed) Find the probability that the number that say they would feel secure is more than live (Round to three decimal places as needed) Find the probability that the number that say they would feel secure is at most five (Round to three decimal places as needed)Explanation / Answer
Each outcome is independent of the other and there are exactly two outcomes
Hence X is binomial with p = 0.7 and n =8
Probabilities
P(X=r) = 8C4 (0.7)r(0.3)8-r
P(X=5) = 0.2541 = 0.254
b) P(X>5) = 0.5517 = 0.552
c) P(X<=5) = 0.4482 = 0.448