4 marksChallenge
A factory uses two machines, A and B, to produce items. Machine A produces a proportion 0.75 of the items, and machine B produces the rest. The probability that an item from machine A is defective is 0.2, and the probability that an item from machine B is defective is 0.6. A randomly chosen item is selected. Find the probability that it is defective.
- (a)[4]
Calculate the probability that a randomly chosen item is defective.
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