The time for an epoxy to cure can be treated as a random variable having a normal distribution with a mean of 30 seconds. Find the standard deviation if the probability is 0.2 that it will take on a value greater than 39.2 seconds I am designing a flow reactor and need glass tubes with an inside diameter of 0.300 0.005 inch. The tubes may be considered a random variable having a normal distri- bution with / = 0.302 inch and o = 0.003 inch. What percentage of these tubes will meet my specifications? Given the following table of the joint pmf for two variables X and Y: y 0 1 2 0.10 0.1 0.2 X 0.08 0.2 0.06 0.06 0.14 0.30 . What is P(X=1 and Y=1)? . What is (X