noob question on combinations/probability (1 Viewer)

RishBonjour

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A squad of 8 is chosen from 3 baseball teams with 10 players in each team.

Find the probability that joe from team B and Dan from team A will be chosen

explanations would be good thanks :)

answer is 1/10
 

Shadowless

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Are you sure it's '1/10'? I'm getting something different. =(
 

Sy123

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Total number of combinations:

30C8

Numnber of combinations with Joe and Dan (it doesnt matter what teams they are on because we are picking from the group as a whole, if it were to say, pick 3 from A 4 from B and 1 from C then it does matter what teams they are on, but not in this case)

pick the 6 from remaining 28

28C6 * 2C2

Put them over each other

 

Shadowless

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Total number of combinations:

30C8

Numnber of combinations with Joe and Dan (it doesnt matter what teams they are on because we are picking from the group as a whole, if it were to say, pick 3 from A 4 from B and 1 from C then it does matter what teams they are on, but not in this case)

pick the 6 from remaining 28

28C6 * 2C2

Put them over each other

Hmm... how come it's not 30 P 8 as the sample space but rather, 30 C 8?
 

Skeptyks

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The order that the 8 people are chosen from the 30 does not matter.
 

RishBonjour

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Total number of combinations:

30C8

Numnber of combinations with Joe and Dan (it doesnt matter what teams they are on because we are picking from the group as a whole, if it were to say, pick 3 from A 4 from B and 1 from C then it does matter what teams they are on, but not in this case)

pick the 6 from remaining 28

28C6 * 2C2

Put them over each other


thats the answer I got. But its a question from maths in focus. it says 1/10 at the back :/

and shadowless--> you are choosing 8 people, not arranging thats why.
 

Shadowless

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thats the answer I got. But its a question from maths in focus. it says 1/10 at the back :/

and shadowless--> you are choosing 8 people, not arranging thats why.
OH... wow... wish me luck in the exam guys LMAO
 

Timske

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I hope the last q is not on binomial or probability
 

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