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Total ways to pick any 3 people from 8 is 56 (8C3)
Now count committees breaking the rules:
1) Aly and Ben + pick 1 from the remaining 6 ---> 6 Bad committees
2) Cam and Dan together + 1 ---> 6 bad committees
1 Committee can't break both rules at once since that would need Ally, Ben, Cam and Dan all in one 3 person group which is impossible. Therefore no overlap and 6+6= 12 bad committees. Valid commitees are 44 (56 minus 12)
probability of x/y=44/56=11/14. Hence x=11 and y=14
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Total number eof candidates =8
ABCDEFGH
A and B are incompatible
C and D are incompatible

If three candidates are chosen at random, the probability that the selected candidates form a valid committee is X / Y , where the fraction is expressed in simplest form.

Total committee can be formed =8C3= 56
Incompatible committee involving AB or CD together = 1*6C1+1*6C1 =12
X=56-12 =44

Required Fraction= X/Y=44/56 =11/14
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Without any restrictions all the possible way to choose a team is 8C3= 56
.:Y=56

Now considering valid teams,
Case 1. None from A,B,C, D is in the team,
No of ways, 4C1=4 ways

Case 2. A & B is not there C or D is in the team.
No. ways, 4C2 *2= 6*2=12 ways (Multiplied by 2, since any of C or D can be there )

Case 3. C & D is not there but A or B is there in the team.
No of ways, 4C2 *2 = 6*2=12 ways (Multiplied by 2 since any of A or B can be there)

Case 4. A or B there, C or D there, and one more person from rest is there.
No. of ways, 2C1 *2C1* 4C1=2*2*4=16 ways

X=4+12+12+16=44

X/Y= 44/56=11/14


Bunuel
A company is forming a three-person leadership committee from a pool of eight qualified candidates: Aly, Ben, Cam, Dan, Emi, Fay, Gia, and Hal. Due to conflicts of interest, two pairs of candidates are incompatible: Aly and Ben cannot both serve on the committee together, and Cam and Dan cannot both serve on the committee together. A committee is considered valid only if its three members do not include either of these pairs of incompatible candidates.

Consider the following incomplete sentence:

If three candidates are chosen at random, the probability that the selected candidates form a valid committee is X / Y , where the fraction is expressed in simplest form.

Select for X and Y values that are consistent with the information provided. Make only two selections, one in each column.
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Bunuel
A company is forming a three-person leadership committee from a pool of eight qualified candidates: Aly, Ben, Cam, Dan, Emi, Fay, Gia, and Hal. Due to conflicts of interest, two pairs of candidates are incompatible: Aly and Ben cannot both serve on the committee together, and Cam and Dan cannot both serve on the committee together. A committee is considered valid only if its three members do not include either of these pairs of incompatible candidates.

Consider the following incomplete sentence:

If three candidates are chosen at random, the probability that the selected candidates form a valid committee is X / Y , where the fraction is expressed in simplest form.

Select for X and Y values that are consistent with the information provided. Make only two selections, one in each column.
Total no. of committees we can form is 8C3 = 56
we calculate the no. of invalid committees that can be formed based on given conditions
1. Commitees with A and B = 6, similarly
2. Committees with C and D = 6
Subtracting the sum from 56 we get 56-6-6 = 44 valid committes
hence the probability = 44/56 = 11/14
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IMO : x= 11, y=14
condition 1 : AB cant be together
condition 2: CD cant be together
therefore, all the following possibilities will be :
choosing 3 from the remaining EFGH= 4C3= 4
choosing 2 from EFGH and Choosing 1 from A or B (but none from CD)= 4C2 *2C1 = 12
choosing 2 from EFGH and choosing 1 from C or D (but none from AB) = 4C2 * 2C1 = 12
choosing 1 from EFGH and choosing 1 from A or B and choosing 1 from C or D = 4C1 * 2C1 * 2C1 = 16

calculating the total possibilities = 4 + 12+12+16 = 44


now the denominator , choosing 3 from 8 options = 8C3 = 56
therefore x/y =44/56 ==> 11/14.
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We know that the company is forming a 3 person leadersup committee from 8 candidates
Aly,Ben,Cam,Dan,Emi,Fay,Gia and Hal

Among these, Aly and Ben cant serve on the committee together
Similarly, Cam and Dan also cant serve together

We need probability that the selected candidates form a valid committee X/Y in its simplest form

There are 8 candidates
=> Number of ways to choose 3 candidates = 8C3 = 8*7*6/3*2*1 = 56

Possible combinations when Aly and Ben together = 6
Possible combinations when Cam and Dan together = 6
Total invalid committees = 6+6 = 12
Total valid committees = 56 - 12 = 44

=> Probability of selected committees form a valid committee = 44/56 = 11/14

=> X/Y = 11/14
X = 11
Y = 14
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Total committe possible without any condition = 8C3 = 56

Let ABX..X can be chosen in 6C1=6 ways
Let CDX ..X can be chosen in 6C1=6 ways

Total 56-12=44 ways

Prob=44/56 = 11/14

X=11
Y=14
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Total ways to pick 3 people from 8
C(8,3)=56

Counting "Bad" or the committies that we dont want
1. Commities with both Aly and Ben : 1 more from the other 6 people = 6 bad commties
2. Commities with both Cam and Dan : same thung = 6 bad Commities
3. Can a committee ave both problems at once (Aly+Ben+Cam+Den)- but we want to only pick 3 . so no overlap

Total Bad = 6+6 =12
Good (Valid) Committies= 56-12 : 44
Probability : 44/56 : 11/14

x: 11 and y:14
Bunuel
A company is forming a three-person leadership committee from a pool of eight qualified candidates: Aly, Ben, Cam, Dan, Emi, Fay, Gia, and Hal. Due to conflicts of interest, two pairs of candidates are incompatible: Aly and Ben cannot both serve on the committee together, and Cam and Dan cannot both serve on the committee together. A committee is considered valid only if its three members do not include either of these pairs of incompatible candidates.

Consider the following incomplete sentence:

If three candidates are chosen at random, the probability that the selected candidates form a valid committee is X / Y , where the fraction is expressed in simplest form.

Select for X and Y values that are consistent with the information provided. Make only two selections, one in each column.
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A company is forming a three-person leadership committee from a pool of eight qualified candidates: Aly, Ben, Cam, Dan, Emi, Fay, Gia, and Hal. Due to conflicts of interest, two pairs of candidates are incompatible: Aly and Ben cannot both serve on the committee together, and Cam and Dan cannot both serve on the committee together. A committee is considered valid only if its three members do not include either of these pairs of incompatible candidates.

Consider the following incomplete sentence:

If three candidates are chosen at random, the probability that the selected candidates form a valid committee is X / Y , where the fraction is expressed in simplest form.

Select for X and Y values that are consistent with the information provided.

A and B can't go together and C and D can't go together.

So, the probability of valid cases= 1-probability of invalid cases
=1-([(AB)+(CD)]/Total)
=1-((6C1+6C1)/8C3)=1-(3/14)=11/14
X=11, Y=14
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