Statistics and Discrete distributions

[amai]

Homework Statement

The probabilities of blood types O, A, B and AB are 0.46, 0.39, 0.12, 0.03 respectively.
If a clinic is seeking either type O or B from six random individuals, what is the probability that at least 2 people have the desired blood type?

Homework Equations

The Attempt at a Solution

I'm not really sure where to start. From the questions, I don't think it's a binomial distribution or a poisson distribution. All i have so far is...

Where X=people with the desired blood type

P(X≥ 2)=1-P(0)-(P(1)

Any suggestions?

 

[Mentallic]

Since the probability of being O is 0.46 and the probability of being B is 0.12, what is the probability of being either O or B?

What is the probability of not being either O or B, or in other words, what is the probability of being A or AB?

 

[pasmith]

Homework Statement

The probabilities of blood types O, A, B and AB are 0.46, 0.39, 0.12, 0.03 respectively.
If a clinic is seeking either type O or B from six random individuals, what is the probability that at least 2 people have the desired blood type?

Homework Equations

The Attempt at a Solution

I'm not really sure where to start. From the questions, I don't think it's a binomial distribution

You are conducting six independent trials, in which success in a trial is defined as "this person has type O or B blood". That gives you a binomial distribution.