This is an example of a random variable that follows Bernoulli distribution.
Whenever you perform
experiments, with probability
of success, the provability of havin
successes is

In this case, you have
(you choose a sample of 3 candidates),
(30% of candidates have a degree in economics) and we want
to be at least one.
One way to solve this is to consider that

But it is much quicker to observe that

And we have

So, the probability that at least one of them has a degree in economics is
