In a factory, machines AAA, B B\,B and C C\,C are all producing metal rods of the same length. Machine A A\,A produces 35% of the rods, machine B B\,B produces 25% and the rest are produced by machine CCC. Of their production of rods, machines AAA, B B\,B and C C\,C produce 3%, 6% and 5% defective rods respectively.
Draw a tree diagram to represent this information.
Find the probability that a randomly selected rod is
(i) produced by machine A A\,A and is defective,
(ii) is defective.
Given that a randomly selected rod is defective, find the probability that it was produced by machine CCC.
Practise Edexcel A Level Old Maths Probability with exam-style questions for A Level Old Maths. 11 questions, matched to the Edexcel A Level Old Maths (9371) specification and written in Unit exams C1, C2, C3 and C4 plus two applied units (e.g. S1 and M1) style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.