Two cards are drawn at random in succession with replacement from a deck of 52 well-shuffled cards. Find the probability of getting both ‘Aces’.
Two cards are drawn at random in succession with replacement from a deck of 52 well-shuffled cards. Probability of getting both ‘Aces’ is
(A) $\dfrac{1}{169}$
(B) $\dfrac{2}{169}$
(C) $\dfrac{1}{13}$
(D) $\dfrac{2}{13}$
(GATE 2007)
Answer: (A) $\dfrac{1}{169}$
Explanation:
Let $E_1$ and $E_2$ be the events of getting 'ace' in the first and the second drwans respectively.
Here, two cards are drawn with replacement.
Hence, the events $E_1$ and $E_2$ are independent.
Now, $P(E_1) = \dfrac{^4C_1}{^{52}C_1} = \dfrac{4}{52}$
and $P(E_2) = \dfrac{^4C_1}{^{52}C_1} = \dfrac{4}{52}$
Therefore, the required probability is
$= P(E_1) \times P(E_2)$
$= \dfrac{4}{52} \times \dfrac{4}{52}$
$= \dfrac{1}{169}$
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