IB Mathematics: Analysis & Approaches Paper 1 · SL (no calculator) · exams to Nov 2028 practice papers
SL · 80 marks · 1h 30m · Section A short + Section B long. Each generated paper follows the SL & HL Paper 1 · SL (no calculator) · exams to Nov 2028 format, with the same number and style of questions as the real exam, and comes with an IB-style mark scheme.
Machines A, B and C produce 60%, 25% and 15% of the items made in a factory. The percentages of defective items they produce are 1%, 4% and 6% respectively. An item is chosen at random.
(a)
Find the probability that the item is defective.
[3]
(b)
Given that the item is defective, find the probability that it was made by machine C.
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