1. Let X denote the mean of a random sample of size 100 from a distri bution that is x2(50). Compute an approximate value of Pr (49 <>X 51).
2. Let X denote the mean of a random sample of size 128 from a gamma distribution with ex = 2 and p = 4. Approximate Pr (7 <>X 9).
3. Let Y be b(72, !). Approximate Pr (22 Y 28).
4. Compute an approximate probability that the mean of a random sample of size 15 from a distribution having p.d.f. f( x) = 3x2, 0 x 1, zero elsewhere, is between Iand i.