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A bag contains 3 red and 2 white identical balls. lf 2 ba...

A bag contains 3 red and 2 white identical balls. lf 2 balls are picked at random from the bag, one after the other and with replacement, find the probability that they are of different colours

A.

\(\frac{36}{625}\)

B.

\(\frac{16}{625}\)

C.

\(\frac{12}{25}\)

D.

\(\frac{13}{25}\)

Correct answer is C

Prob(RW or WR) = Prob(RW) + Prob(WR)
\(Prob(R) = \frac{3}{5}:Prob(W) = \frac{2}{5}\\
Prob(RW\hspace{1mm}or\hspace{1mm}WR)=\frac{3}{5}\times\frac{2}{5}+\frac{2}{5}\times \frac{3}{5}\\
\frac{6}{25}+\frac{6}{25}=\frac{12}{25}\)