A box contains 20 defective items and 80 nondefective items.

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A box contains 20 defective items and 80 nondefective items. If two items are selected at random without replacement, what will be the probability that both items are defective?

1. 1
  5
2. 1
  25
3. 20
  99
4. 19
  495

Correct Option: D

P(Both defective) =	N(Both defective)
	Sample space

=		²⁰C₂	=	19
		¹⁰⁰C₂		495