00:01
In this question, we're given a standard deck of 52 playing cards, and one card is randomly selected from the deck.
00:07
In part a, we want to find probability of randomly selecting a king or nine.
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Now, take note that a king and a nine, there are mutually exclusive cases or mutually exclusive events.
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So all you need to do is to add the probability for both events together, since they have nothing common between them.
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Now in probability n is times, set notation is intersect.
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All is plus set notation is union.
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So in this case, probability are randomly selecting a king.
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So we just want to get probability of getting a king.
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Or, all means plus in probability.
00:52
So plus probability of getting a nine.
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And there's nothing else because they are mutually exclusive.
00:59
So it's either this case or this case.
01:06
So probability of getting a king, we know there are four kings in the whole deck.
01:10
So it's four kings out of 52 cards plus probability of getting a nine.
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We know there are four nines.
01:18
So it's four out of 52 cards also.
01:21
And so the answer is two out of 13 or 0 .154, three decimal place.
01:37
Now in b, we want to find.
01:39
Probability of randomly selecting a king, a nine or an ace.
01:45
Now again, these three mutually exclusive case because you can't be a king and a nine and an ace at the same time and so on and so forth.
01:54
So three mutually exclusive case again will add up the total probability for king, a nine and an ace.
02:03
So we'll be getting probability of a king or is plus probability of a nine or, or, probability of an ace.
02:19
So probability of a king and a knight already, we have it here, is 2 out of 13.
02:26
So these two cases is 2 out of 13.
02:29
We're going to add to probability of an ace...