Nhận biết (M1)

There are two boxes of the same product. The first box contains 10 items, 2 of which are defective. The second box contains 10 items, 3 of which are defective. 1 product is taken from the first box, and 2 products are taken from the second box.

(a) Find the probability that the three products drawn are non-defective.

(b) Let denote "the number of defective products in the three products selected". Find , the expected value of .

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