Question 1007465
A box contains 15 transistors, 3 of which are defective. If 3 are selected at random.  the probability that.
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Assuming you don't put them back (w/o replacement):
a. all are defective
= (3/15)*(2/14)*(1/13)
= 1/455
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b. none are defective
= (12/15)*(11/14)*(10/13)
= 220/455
= 44/91