Question: A random sample of 1000 eligible voters is drawn, and X = number who actually voted in the last election. It is known that 60% of all eligible voters did vote.
a. Use the normal approximation to the binomial distribution to approximate P(X ≤ 620), the probability that 620 or fewer individuals in the sample actually voted.
b. Use statistical software, Excel, or a graphing calculator to find the exact binomial probability that 620 or fewer individuals in the sample actually voted.