SOLUTION: Could someone please help me? Answer the following: (A) Find the binomial probability P(x = 6), where n = 15 and p = 0.70. (B) Set up, without solving, the binomial probabili

Algebra ->  Probability-and-statistics -> SOLUTION: Could someone please help me? Answer the following: (A) Find the binomial probability P(x = 6), where n = 15 and p = 0.70. (B) Set up, without solving, the binomial probabili      Log On


   



Question 622065: Could someone please help me?
Answer the following:
(A) Find the binomial probability P(x = 6), where n = 15 and p = 0.70.
(B) Set up, without solving, the binomial probability P(x is at most 6) using probability notation.
(C) How would you find the normal approximation to the binomial probability P(x = 6) in part A? Please show how you would calculate µ and σ in the formula for the normal approximation to the binomial, and show the final formula you would use without going through all the calculations.

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 
Hi,
Note: The probability of x successes in n trials is:
P = nCx* p%5Ex%2Aq%5E%28n-x%29 where p and q are the probabilities of success and failure respectively.
In this case p = .70 & q = .30 and n = 15
nCx = n%21%2F%28x%21%28n-x%29%21%29
P(x = 6) = 21C6(.7)^6(.3)^9 = 5005(.7)^6(.3)^9 = .012
P(x ≤ 6) = P(0) + P(1) + P(2) + P(3) + P(4) + P(5) + P(6)
= (.7)^0(.3)^15 + 2(.7)^1(.3)^14 + 105(.7)^2(.3)^13 + 455(.7)^3(.3)^12 + 1365(.7)^4(.3)^11 + 3003(.7)^5(.3)^10+ 5005(.7)^6(.3)^9
(c) = mu+=+15%2A.70+=+10.5 and
sigma++=sqrt%2815%2A.7%2A.3%29=+1.7748
z = %28x-mu%29%2Fsigma