A purse contains 4 copper coins & , 3 silver coins, second purse contains 6 copper coins &a

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14.Probability

normal

A purse contains $4$ copper coins $\& \, 3$ silver coins, the second purse contains $6$ copper coins $\& \,2$ silver coins. If a coin is drawn out of one of these purses, then the probability that it is a copper coin is :-

A

$\frac{4}{7}$

B

$\frac{3}{4}$

C

$\frac{37}{56}$

D

None

Solution

Required probability $=\frac{1}{2}\left(\frac{4_{C_{1}}}{7_{C_{1}}}+\frac{6_{C_{1}}}{8_{C_{1}}}\right)$

$=\frac{37}{56}$

Standard 11

Mathematics

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(IIT-1998)