Question

If the probability of getting an easy Assignment is 0.4. Find the probability that the 3rd
assignment you get is the first easy assignment (i.e. the earlier two were difficult).

Answer 1

Solution:

The event follows a geometric distribution with the first success coming after the third trial;

$P(X=x) = p(1-p)^{x-1}$

$P(X =3)=0.4(0.6)^2$

=0.144