Bag A contains 2 unbiased and 3 biased coins whereas Bag B contains 3 unbiased and 2 biased coins. A bag is selected at random and 2 coins are taken out simultaneously. The probability, that both coins are unbiased is:
Bag A contains 2 unbiased and 3 biased coins whereas Bag B contains 3 unbiased and 2 biased coins. A bag is selected at random and 2 coins are taken out simultaneously. The probability, that both coins are unbiased is:
Solution
Bag A contains 2 unbiased and 3 biased coins (5 coins total).
Bag B contains 3 unbiased and 2 biased coins (5 coins total).
A bag is selected at random, and 2 coins are taken out simultaneously.
Since either bag can be selected:
The probability of selecting each bag is:
For Bag A with 2 unbiased coins:
Number of ways to select 2 unbiased coins from 2:
Total ways to select 2 coins from 5:
For Bag B with 3 unbiased coins:
Number of ways to select 2 unbiased coins from 3:
Total ways to select 2 coins from 5:
Therefore, the probability that both coins are unbiased is .
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