The normal distribution Exercise 3F 1 For each of the following binomial random variables, X: i state, with reasons, whether X can be approximated by a normal distribution. ii if appropriate, write down the normal approximation to X in the form N(u, 02), giving the values of u and o. a X ~ B(120, 0.6) b X ~ B(20, 0.5) c X ~ B(250, 0.52) d X ~ B(300, 0.85) e X ~ B(400, 0.48) f X ~ B(1000, 0.58) 2 The random variable X ~ B(150, 0.45). Use a suitable approximation to estimate: a P(X - 60) b P(X > 75) c P(65 58) b P(60