State the conditions under which a binomial distribution can be approximated as a normal distribution, and state how the parameters needed would be calculated.

This is a two - part question. The first part is stating the necessary conditions, of which there are two: the number of trials must be large (more than 50), and the probability of success or failure must be close to 0.5. Alternatively, if both np and n(1-p) are larger than 5, then the probability of success or failure condition can be disregarded. The second part of the question revolves around converting the two parameters of the binomial distribution (the number of trials and probability of success) into the two parameters of the normal distribution (mean and variance/Standard Deviation). The mean can be calculated from the parameters of the binomial distribution using the number of trials X the probability of success, and the variance is calculated by multiplying this mean by the value of (1- the probability of success) or the probability of failure. The standard deviation can be found by square rooting the variance.