Question

9. A bag contains 1 green marble and 3 red marbles. 3 times a marble is removed from the bag, its color noted, and then returned. Success is getting a green marble. Find the probability of getting three green marbles.

10. A population has a mean of 60 and a standard deviation of 61. Samples of size 100 are randomly selected. Calculate the standard deviation of the sample distribution X.

11. Tires are found to have a mean life of 800 hours. The standard deviation is 160. A sample of 100 is chosen. Find the probability that 40, 800 < X < 812.

12. A sample of size 100 is chosen from a population. The sample mean is 50 and the standard deviation is 10. Find the upper limit of the 95% confidence interval for the population mean.

Answer 1

green al total=4 Pe green) 1 4 B 10.0156 43 lo l-Go Ge= 61 - 16-1 - 100 Troo la 800 G-160 P (8 do 4 x 432) - P(800-800 800-812) e ST nc nt gn pu 24 160 pic MU ud- bu LA MC au Po szc0.12) P(0.12) 0 (0.00) 0.54776 0.04476 0.5 ba je Bu SIL er bol 12 = 5o S- 10 I-do 0.95 1.96 Zt12 u t sns ad PO so + 1.96 Too 15196