Both of these conditions must be true in order for the assumption that the binomial distribution is approximately normal. In other words, if [tex]np \ge 5[/tex] and [tex]nq \ge 5[/tex] then we can use a normal distribution to get a good estimate of the binomial distribution. If either np or nq is smaller than 5, then a normal distribution wouldn't be a good model to use.
side note: q = 1-p is the complement of probability p
