stats homework please help

Question

Assume that a procedure yields a binomial distribution with a trial repeated  times. Use some form of technology to find the probability distribution given the probability  of success on a single trial.

(Report answers accurate to 4 decimal places.)

kP(X = k)
0
1
2
3
4
5

Answer 1

Hi Ariel,

This is a binomial distribution where:

n=5

p=0.721

You are being asked to fill in the table with probabilities for x=0, x=1, x=2. x=3, x=4 and x=5.

This can be done easily using a TI-84 or similar calculator. For x = 0, press 2nd VARS and scroll down to binompdf. Press enter, and for trials enter 5, for p enter 0.721, and for x enter 0. Press enter 3 times to get your answer = 0.0017.

Repeat the above for x = 1, then for x = 2, etc., to fill in the table.

When you are done, add up all the probabilities and you should get 1. If not, go back and check your calculations or your rounding.

Hope that helps!

If you don't have a scientific calculator that can do this, I can show you another way using formulas.

Steph

Answer 2

P(n=5,k=0) = C(5,0) (0.721)^0 (0.279)^5 = 0.0017

P(n=5,k=1) = C(5,1) (0.721)^1 (0.279)^4 = 0.0218

P(n=5,k=2) = C(5,2) (0.721)^2 (0.279)^3 = 0.1129

P(n=5,k=3) = C(5,3) (0.721)^3 (0.279)^2 = 0.2918

P(n=5,k=4) = C(5,4) (0.721)^4 (0.279)^1 = 0.3770

P(n=5,k=5) = C(5,5) (0.721)^5 (0.279)^0 = 0.1948