one of two coins is selected at random and tossed. The first coin comes up heads with probability p1 and the second coin with probability p2.(A) What is probability that the outcome of toss is heads? (B) what is probability that coin 2 was used given a head occured?

Question

shubhamsrg · Answer

okay.

anonymous · Answer

what are we solving??

anonymous · Answer

one of two coins is selected at random and tossed. The first coin comes up heads with probability p1 and the second coin with probability p2. (A) What is probability that the outcome of toss is heads? (B) what is probability that coin 2 was used given a head occured?

anonymous · Answer

im not understanding what your trying to figure out this does not make sense sorry

phi · Answer

(A) What is probability that the outcome of toss is heads? 

Pr(H)=  Pr(coin1)* Pr(H| coin1) + Pr(coin2)* Pr(H|coin2)

phi · Answer

Using a tree diagram
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phi · Answer

For (b),  given that you see a Head,  the denominator is 0.5*(p1+p2)
the numerator is 0.5*p2.
Pr(coin2 | H) = p2/(p1+p2)

anonymous · Answer

In each lot of 100 items, 2 items are tested, and the lot is rejected if either of the tested items is found defective.
(A)	Find probability of accepting a lot with 5 defective items. Repeat for 10 defective items.
(B)	Recomputed the probabilities in part (A) if items are tested, and a lot is accepted when at most 1 of the 3 tested items is found defective.