1. According to the empirical rule, for a distribution that issymmetric and bell-shaped, approximately _______ of the data valueswill lie within 3 standard deviations on each side of the mean.
2. Assuming that the heights of boys in a high-school basket-ball tournament are normally distributed with mean 70 inches andstandard deviation 2.5 inches, how many boys in a group of 40 areexpected to be taller than 75 inches?
3. Let x be a random variable that represents the length of timeit takes a student to complete Dr. Gill’s chemistry lab project.From long experience, it is known that x has a normal distributionwith mean ? = 3.6 hours and standard deviation ? = 0.5.
Convert each of the following x intervals to standard zintervals.
(a) x ? 4.5 4. (a) __________________________
(b) 3 ? x ? 4 (b) __________________________
(c) x ? 2.5 (c) __________________________
Convert each of the following z intervals to raw-score xintervals.
(d) z ? ?1 (d) __________________________
(e) 1 ? z ? 2 (e) __________________________
(f) z ? 1.5 (f)_ __________________________
