I'm reading my textbook, and I don't follow how the following probability distribution was calculated.

Can you help me understand how we got the f(x) values in the probability distribution? What formulas were used? Is it some kind of counting calculation?

Originally Posted by Fischercr
I'm reading my textbook, and I don't follow how the following probability distribution was calculated.

Can you help me understand how we got the f(x) values in the probability distribution? What formulas were used? Is it some kind of counting calculation?
$f(k)=\dbinom{3}{k}\left( \dfrac{1}{4}\right)^k\left( \dfrac{3}{4}\right)^{3-k}$___$k=0,1,2,3$

$\dbinom{3}{k}=\left( \dfrac{3!}{(k!)(3-k)!}\right)$