An urn contains 4, 000 balls of which 1, 700 are white and 2, 300 are green.
(a) Balls are chosen from the urn 1, 200 times with replacement and
recorded as either green or white. Use Excel’s BINOMDIST to find
the probability that between 900 and 1, 000 green balls are selected.
(b) Now assume 1, 500 balls are chosen from the urn with replacement and are recorded as either green or white. Use Excel to find the probability that exactly 950 white balls are selected.
(c) Redo part (a) and (b), but instead by using the normal approximation. Are these answers a good approximation? Why or why not?