Source: Princeton Review
A dance team with 5 members will perform, 2 dancers at a time, until all the possible combinations of dancers have performed. If each combination dances for 5 minutes, and there are no breaks or interruptions, what is the total running time of the performance?
A. 80 minutes
B. 75 minutes
C. 60 minutes
D. 50 minutes
E. 45 minutes
The OA is D
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A dance team with 5 members will perform, 2 dancers at a
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BTGmoderatorLU
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BTGmoderatorLU wrote:Source: Princeton Review
A dance team with 5 members will perform, 2 dancers at a time, until all the possible combinations of dancers have performed. If each combination dances for 5 minutes, and there are no breaks or interruptions, what is the total running time of the performance?
A. 80 minutes
B. 75 minutes
C. 60 minutes
D. 50 minutes
E. 45 minutes
The OA is D
The number of combinations of dancers is 5C2 = (5 x 4)/2! = 10 and therefore the total running time of the performance is 10 x 5 = 50 minutes.
Answer: D
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deloitte247
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5 members with 2 dancers at a time;
$$Possible\ combination=5_{C_2}=\frac{5\cdot4}{2\cdot1}=\frac{20}{2}=10 ways$$
$$The\ the\ total\ runtime\ of\ 5\ \min utes\ per\ 10\ ways\ =\ 5\cdot10=50\ \min utes\ \ \ \ \ \left(option\ D\right)$$
$$Possible\ combination=5_{C_2}=\frac{5\cdot4}{2\cdot1}=\frac{20}{2}=10 ways$$
$$The\ the\ total\ runtime\ of\ 5\ \min utes\ per\ 10\ ways\ =\ 5\cdot10=50\ \min utes\ \ \ \ \ \left(option\ D\right)$$
