A police department needs new tires for its patrol cars And the probabilities are 0.15, 0.24, 0.03,

Question:

A police department needs new tires for its patrol cars And the probabilities are 0.15, 0.24, 0.03, 0.28, 0.22, And 0.08, respectively, that it will buy Uniroyal tires, Goodyear tires, Michelin tires, General tires, Goodrich tires, or Armstrong tires. Find the probabilities that it will buy
(a) Goodyear or Goodrich tires;
(b) Uniroyal, Michelin, or Goodrich tires;
(c) Michelin or Armstrong tires;
(d) Uniroyal, Michelin, General, or Goodrich tires.