Question

Suppose x has a distribution with u = 85 and 6 = 11. (a) If random samples of size n = 16 are selected, can we say anything about the x distribution of sample means? Yes, the x distribution is normal with mean = 85 and 0 , = 2.75. • No, the sample size is too small. Yes, the x distribution is normal with mean = 85 and x = 11. Yes, the x distribution is normal with mean - 55 and 0 -0.7. (b) If the original x distribution is normal, can we say anything about the x distribution of random samples of size 16? No, the sample size is too small Yes, the x distribution is normal with mean = 85 ando - 11. Yes, the x distribution is normal with mean - 85 and o=0.7. Yes, the x distribution is normal with mean; - 85 and o, -2.75 Find P(81 S XS 36). (Round your answer to four decimal places.)

Answer 1

Given l=85 0-12 n=16 a) No the Sample size : two Somall distribution is normal with mean b) yes the u (1 di = 1=85 Ti - 2.75 Ophion D 81-85 C) P(81<ā 286) PLS << 86-85 275 2175 1 =P[te . PE 1.4527<0.36] 2.75 From z table we get P[720.36 ) -P[22 -1.45] 06406 - 0.0736 = 0.567) P (81 CT <86) -0.5671