A purse contains 2 silver 4 copper coins. A second purse contains 4 silver 3 copper coins. If a coin is pulled at random from one of the two purses, what is the probabilty that it is a silver coin?
Since we have 2 purse so probability of choosing a purse is 1/2
Now P[coin is silver]=P[1st purse is chosen and coin is silver]+P[2nd purse is chosen and coin is silver]
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Now P[coin is silver]=P[1st purse is chosen and coin is silver]+P[2nd purse is chosen and coin is silver]
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