69. The sample average unrestrained compressive strength for 45 specimens of a particular type of brick was com- puted to be 3107 psi, and the sample standard deviation was 188. The distribution of unrestrained compressive strength may be somewhat skewed. Does the data strong- ly indicate that the true average unrestrained compres- sive strength is less than the design value of 3200? Test using a = .001.

Suppose the lengths of human pregnancies are normally distributed with μ = 266 days and o 16 days. Complete parts (a) and (b) below. (a) The figure to the right represents the normal curve with μ = 266 days and o=16 days. The area to the right of X = 290 is 0.0668. Provide two interpretations of this area. Provide one interpretation of the area using the given values. Select the correct choice below and fill in the answer boxes to complete your choice. (Type integers or decimals.) O A. The proportion of human pregnancies that last less than OB. The proportion of human pregnancies that last more than days is days is Provide a second interpretation of the area using the given values. Select the correct choice below and fill in the answer boxes to complete your choice. (Type integers or decimals.) O A. The probability that a randomly selected human pregnancy lasts more than OB. The probability that a randomly selected human pregnancy lasts less than days is days is or more than and days…

A normal distribution has a mean of u= 80 with o= 12. Find the following proportions with the given score: (X < 74). Be sure to illustrate the normal distribution and shade in the region in question.

At a certain high school, every freshman has his or her height The freshman boys have a mean height of 65.2 inches and a standard deviation of 3.2 inches. The freshman girls have a mean height of 63.5 inches and a standard deviation of 2.7 inches. The proportion of of freshman girls has heights between 60 to 65 inches is 0.6133. What is the interpretation of this normal density area? (i) The proportion of freshman having heights between 60 to 65 inches is 0.6133 (ii) The probability that a randomly selected freshman girl have heights between 60 to 65 inches is 0.6133 or 61.33% Oboth (i) and (ii) are correct We can not interpret the given area..