A card is randomly drawn from a deck of 52 cards. What is the probability getting a five of Spade or Club?
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Solution 1
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all number of cards, $n\left(S\right)$ = 52
E= event of getting a five of Spade or Club
$n\left(E\right)$ = 2[ a five of Club, a five of Spade = 2 cards]
$\text{P(E) = }\dfrac{\text{n(E)}}{\text{n(S)}} = \dfrac{2}{52} = \dfrac{1}{26}$
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Solution 2
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Total number of cards = 52
Total number of Spade Cards of Number 5 = 1
Total number of Club Cards of Number 5 = 1
P[Spade Cards of Number 5] = $\dfrac{1}{52}$
P[Club Cards of Number 5] = $\dfrac{1}{52}$
Here, clearly the events are mutually exclusive events.
By Addition Theorem of Probability, we have
P[Spade Cards of Number 5 or Club Cards of Number 5]
= P[Spade Cards of Number 5] + P[Club Cards of Number 5]
$= \dfrac{1}{52} + \dfrac{1}{52} = \dfrac{1}{26}$