Answer:
(a) 0.2824
(b) 0.0002441
Step-by-step explanation:
Assuming that the population is large enough to behave as a binomial distribution (between whites and non-whites), the probability of 12 out of 12 juros being white is:

Where p(w) is the proportion of the population that is white:
(a) for p = 0.90

The probability is 0.2824.
(b) for p = 0.50

The probability is 0.0002441.
Every single one of those polynomials factors. When factored, your expression looks like this:

. When you cancel the like factors out, what you're left with is this:

. That means that b = 9, c = 1, and d = -2
<span>[-4+3]-8
= </span><span>-1 - 8
= -9
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