A supplier provides 70% of a shop's lamps and another supplier provides the rest. For the first supplier, 3% of lamps are faulty. For the second supplier, 8% are faulty. A faulty lamp is independently detected by an inspection with probability 0.90. A non-faulty lamp is incorrectly rejected with probability 0.02.
Given that a randomly selected lamp is rejected, find the probability that it came from the second supplier.
164 exam-style questions on WJEC A Level Maths 4.1 Probability (A-level only), covering 4.1.1 Probability (A-level only), 4.1.2 Probability (A-level only), and 4.1.3 Probability (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.