A shop stocks tinned cat food of two makes, A and B, and two sizes, large and small. Of the stock, 70%

Question

is of brand A, 30% is of the brand B. Of the tins of brand A, 30% are of the small size, whilst of the tins
of brand B, 40% are of the small size. Determine the probability that
(a) a tin chosen at random from the stock will be of the small size.
(b) a small tin chosen at random from the stock will be brand A.

Answer 1

If the events are independent, the probability of both/all events occurring is determined by multiplying the probabilities of the individual events.

A. .3 * .4 = ?

B. .7 * .3 = ?