Sum and product lawsEdexcel International A Level Maths: Mind map

Exam questions on Sum and product laws

1. Events $A$ and $B$ are such that $P(A)=0.4$, $P(B)=0.5$ and $P(A\cap B)=0.15$.
   Find the probability that neither $A$ nor $B$ occurs.2 marks
2. A bag contains 5 red discs and 3 blue discs. Two discs are taken from the bag at random, one after the other, without replacement.
   Find the probability that at least one of the two discs is red.2 marks
3. A factory has two machines. Machine $X$ makes 60% of the components and machine $Y$ makes the other 40%. Each component from $X$ is defective with probability 0.05, and each component from $Y$ is defective with probability 0.02, independently of all others.
   Find the probability that a component chosen at random from the factory's output is defective.3 marks