00:02
From the question, our experiment is a duck of 52 cars is there to four players.
00:09
So 13 cars each.
00:11
We call these four players north, east, south and west.
00:16
So let's event a, b, north and south together having eight spades.
00:27
So eight spades.
00:31
And event b, b.
00:34
Each which have three spades so we want to find a probability of b given that event a has already occurred from our question so the outcome space let's say s contains every division of do those 52 cuts into the four other growth of 13 so so if all event in s are considered equally likely, then probability of event a is a subset of the universal certificate s and a probability of a would then be given as the length of a by the length s.
01:38
So where this denote the number of elements in a, hence this will also denote the number of elements in s.
01:58
So the number of elements in s given as this will be given by 52, choose 13 and 39, choose 13 then 29 choose 13 which will be equal to 52 factorial over 13 factorial to the power 4 so it's like choosing 13 cars for north then for east then for south and the remaining cars goes to west the the formula for conditional probability for a, b events is given us b, probability of b given a is equal probability of a intersection b, all over probability of a.
03:03
So we will have to find the various probabilities.
03:09
So let's count the number of elements in a.
03:14
So we choose first the cards for north and south.
03:18
The eight space can be chosen in 13, choose a ways.
03:27
And the remaining 18 cards for the non -spates is 39, 18 ways.
03:37
Okay.
03:40
Then determine the north card for those 26 will be 26, choose 13 ways.
03:50
So whichever choice are done in choosing the cars for north and south, the remaining 26 cars can be distributed among east and west in any of the 26 choose 13 ways.
04:06
So using the formula, using the formula probability of a is given by a number of elements in a or by the number of elements in the universal asset...