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From a 9-player softball team, 4 will be selected randomly t
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10 Apr 2020, 09:23
10 Apr 2020, 09:23
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Question Stats:
90% (00:51) correct
9% (00:37) wrong based on 44 sessions
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From a 9-player softball team, 4 will be selected randomly to be interviewed by reporters after the game. How many different groups are possible for the interview?
A. 56
B. 63
C. 84
D. 105
E. 126
Kudos for the right answer and explanation
A. 56
B. 63
C. 84
D. 105
E. 126
Kudos for the right answer and explanation
Re: From a 9-player softball team, 4 will be selected randomly t
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10 Apr 2020, 09:37
10 Apr 2020, 09:37
1
let the players be : A B C D E F G H I
Since , selecting A, B ,C & D is same as selecting D, C ,B & A .
Therefore order is not important. Hence its a combination problem.
Thus, ways in which group of 4 players can be selected out of 9 players are :
* 9C4 =( 9!)/(4!)x(9-4)!
* 9Cc4= ( 9!)/(4!)(5!)
* 9C4= (9x8x7x6)x(5!)/(4x3x2x1)x(5!)
* simplifying this we get
* 9C4= 3x1x7x6=126
Ans: Number of ways a group of 4 players can be selected for an interview out of 9 players = 126 ( Option E)
Since , selecting A, B ,C & D is same as selecting D, C ,B & A .
Therefore order is not important. Hence its a combination problem.
Thus, ways in which group of 4 players can be selected out of 9 players are :
* 9C4 =( 9!)/(4!)x(9-4)!
* 9Cc4= ( 9!)/(4!)(5!)
* 9C4= (9x8x7x6)x(5!)/(4x3x2x1)x(5!)
* simplifying this we get
* 9C4= 3x1x7x6=126
Ans: Number of ways a group of 4 players can be selected for an interview out of 9 players = 126 ( Option E)
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Re: From a 9-player softball team, 4 will be selected randomly t
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11 Apr 2020, 09:35
11 Apr 2020, 09:35
1
Carcass wrote:
From a 9-player softball team, 4 will be selected randomly to be interviewed by reporters after the game. How many different groups are possible for the interview?
A. 56
B. 63
C. 84
D. 105
E. 126
Kudos for the right answer and explanation
A. 56
B. 63
C. 84
D. 105
E. 126
Kudos for the right answer and explanation
Since the order in which we select the four players does not matter, we can use combinations
We can select four players from nine players in 9C4 ways
9C4 = (9)(8)(7)(6)/(4)(3)(2)(1)
= (9)(7)(6)/(3)(1)
= (3)(7)(6)
= 126
ASIDE: Here is a brief video covering a strategy to quickly calculate combinations:
Cheers,
Brent
