A machine part is assembled by fastening four components of type
A and one component of type B end-to-end. The lengths, in mm, of
components of type A are independent N (14, 0.36) random variables,
while the lengths, in mm, of components of type B are N(40, 0.25)
random variables.
a.What are the mean and variance for the total length of the
assembled part?
b.What is the probability that the assembled part has a length
less than 98 mm?