Three machines called A, B and C, produce 43%, 26% and 31% of the total production of
a company, respectively. Furthermore, it has been detected that 8%, 2% and 1.6% of the product
manufactured by these machines is defective.
a) What is the probability that a product is not defective?
b) A product is selected at random and found to be defective, what is the
probability that it was manufactured on machine B?