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Also Killer u missed out the possibilities of 0, 8 and 8,0. Moreover u missed out the possibilites of 8 people being divided into more than 2 groups.
1. The stem clearly state "Eight people are to be divided into two groups. What is the probability that there will be 4 in each groups?"
2. For me 0,8 means that you don't have two groups only one group of eight people. I don't like philosophical questions. (i.e. "what is a group of people ?").
Also Killer u missed out the possibilities of 0, 8 and 8,0. Moreover u missed out the possibilites of 8 people being divided into more than 2 groups.
1. The stem clearly state "Eight people are to be divided into two groups. What is the probability that there will be 4 in each groups?"
2. For me 0,8 means that you don't have two groups only one group of eight people. I don't like philosophical questions. (i.e. "what is a group of people ?").
3. what's the OA.
Sorry for the confusion. I think I explained it the wrong way.
THere is my actual expanation.
Dividing people into 2 groups of 4 requires choosing 4 people from 8. So 8C4 is the number of the ways of forming 2 groups of 4. So far so good.
Now for the total number of ways of forming 2 groups. This can be as you said groups of 1,7, and 7,1 2,6 and 6,2 3,5 and 5,3 4,4 and the philosophical 0,8 and 8,0. Now I feel we need to calculate the number of ways we can get these combinations. So for 1,7 it is 8C1*8C7. Similarly for 2,6 it is 8C2*8C6, for 5,3 it is 8C3*8C5, for 8,0 it is 8C0*8C8 and for 4,4 it is 8C4*8C4
Now on adding these we get (8C1)^2 + (8C2)^2 + (8C3)^2 + (8C4)^2 and the philosophical (8C0)^2
I guess the answer wud be 8C4/((8C1)^2 + (8C2)^2 + (8C3)^2 + (8C4)^2 and the philosophical (8C0)^2)
Now to take it one step further if the order of the groups matters then it is
8C4/2*((8C1)^2 + (8C2)^2 + (8C3)^2 + (8C4)^2 and the philosophical (8C0)^2)
Also Killer u missed out the possibilities of 0, 8 and 8,0. Moreover u missed out the possibilites of 8 people being divided into more than 2 groups.
1. The stem clearly state "Eight people are to be divided into two groups. What is the probability that there will be 4 in each groups?"
2. For me 0,8 means that you don't have two groups only one group of eight people. I don't like philosophical questions. (i.e. "what is a group of people ?").
3. what's the OA.
Sorry for the confusion. I think I explained it the wrong way.
THere is my actual expanation.
Dividing people into 2 groups of 4 requires choosing 4 people from 8. So 8C4 is the number of the ways of forming 2 groups of 4. So far so good.
Now for the total number of ways of forming 2 groups. This can be as you said groups of 1,7, and 7,1 2,6 and 6,2 3,5 and 5,3 4,4 and the philosophical 0,8 and 8,0. Now I feel we need to calculate the number of ways we can get these combinations. So for 1,7 it is 8C1*8C7. Similarly for 2,6 it is 8C2*8C6, for 5,3 it is 8C3*8C5, for 8,0 it is 8C0*8C8 and for 4,4 it is 8C4*8C4
Now on adding these we get (8C1)^2 + (8C2)^2 + (8C3)^2 + (8C4)^2 and the philosophical (8C0)^2
I guess the answer wud be 8C4/((8C1)^2 + (8C2)^2 + (8C3)^2 + (8C4)^2 and the philosophical (8C0)^2)
Now to take it one step further if the order of the groups matters then it is
8C4/2*((8C1)^2 + (8C2)^2 + (8C3)^2 + (8C4)^2 and the philosophical (8C0)^2)
Hello dahcrap - I like your thinking but I recommend that you will use the "occam's razor" on this one - don't forget you have only two minutes !!!
Also Killer u missed out the possibilities of 0, 8 and 8,0. Moreover u missed out the possibilites of 8 people being divided into more than 2 groups.
1. The stem clearly state "Eight people are to be divided into two groups. What is the probability that there will be 4 in each groups?"
2. For me 0,8 means that you don't have two groups only one group of eight people. I don't like philosophical questions. (i.e. "what is a group of people ?").
3. what's the OA.
Sorry for the confusion. I think I explained it the wrong way.
THere is my actual expanation.
Dividing people into 2 groups of 4 requires choosing 4 people from 8. So 8C4 is the number of the ways of forming 2 groups of 4. So far so good.
Now for the total number of ways of forming 2 groups. This can be as you said groups of 1,7, and 7,1 2,6 and 6,2 3,5 and 5,3 4,4 and the philosophical 0,8 and 8,0. Now I feel we need to calculate the number of ways we can get these combinations. So for 1,7 it is 8C1*8C7. Similarly for 2,6 it is 8C2*8C6, for 5,3 it is 8C3*8C5, for 8,0 it is 8C0*8C8 and for 4,4 it is 8C4*8C4
Now on adding these we get (8C1)^2 + (8C2)^2 + (8C3)^2 + (8C4)^2 and the philosophical (8C0)^2
I guess the answer wud be 8C4/((8C1)^2 + (8C2)^2 + (8C3)^2 + (8C4)^2 and the philosophical (8C0)^2)
Now to take it one step further if the order of the groups matters then it is
8C4/2*((8C1)^2 + (8C2)^2 + (8C3)^2 + (8C4)^2 and the philosophical (8C0)^2)
Hello dahcrap - I like your thinking but I recommend that you will use the "occam's razor" on this one - don't forget you have only two minutes !!!