How to compute Binomial Distribution (TIBA - 02)?

[GLope5462]

Hi, could someone help explaining How to compute Binomial Distribution (TIBA - 02)?

 

[gsarm1987]

1. Identify n, the number of trials.
2. Identify p, the probability of success on a single trial.
3. Identify r, the number of successes you want.
4. Plug these values into the formula: P(X=r)=nCr * (P^r) * (1−p)^(n−r). This is also called the probability mass function (PMF) denoting probability of r outcomes,
5. Calculate nCr, P^k, and (1−P)^(n-k), then multiply them together.

for nCr, assume n=10 and r =2. in BAII plus calc, you do it by pressing 10 then 2ND then + then 2 and you'll get 45

by analogy say we had 10 balls in a bag, there are 2 blue and 8 red. we ran X number of trials each time blind folded trying to pick a ball and see what we get. probability of red ball would be P = 2/10, so now input the numbers say we ran the trial 20 times. say in this whole process you want to get 15 red balls (r =15)