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# counting problem

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Annie's soccer team is conducting a passing drill in which each of the 11 members of the soccer team must pass the ball to each of the other members exactly three times. How many times must the ball be passed before the passing drill is over?

I got

$$\frac{11*10}{2}*3=165$$

but I'm not sure about it.

Does order of which the ball is passed matter in this problem? Let's say that person A passes it to person B. When person B passes it to person A, does that count as a different pass?

Guest Aug 19, 2018
#1
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Each member of my team  (11) will have to pass it 3 ttimes to EACH member of the other team

so that is  11 x 3 x 11       If we assume the ball is passed directly back (completing the passing for the OTHER team)

11 x 3 x 11 x 2 = 726 passes

Guest Aug 19, 2018
edited by Guest  Aug 19, 2018
#2
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Can you explain how you got the answer? I still don't understand, sorry

Guest Aug 19, 2018
edited by Guest  Aug 19, 2018
#3
+1198
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(There is no “other team” in this question)

Solution:

Each team member passes the ball to ten (10) other players three (3) times, and this happens for each of the eleven (11) players.  10 * 3 * 11 = 330

The drill completes at 330 passes.

GA

GingerAle  Aug 20, 2018
#4
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Wait, so person A passing it to B is different from B passing it to A, right?

Thanks!

Guest Aug 20, 2018
#5
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A passing it to B is different from B passing it to A, right?

That’s correct. When A passes to B, B is receiving, so that is different from B passing to A.

GingerAle  Aug 20, 2018
#6
+13590
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(There is no “other team” in this question)      TRUE, GA...I misread the Q !   Thnx

ElectricPavlov  Aug 20, 2018
#7
+91027
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Here's another way to see this .....

We want to permute  any 2 of the 11 team members....this will give us all the possible pairings of passes between any two team members

So  P (11,2)   =  110

But since the ball is passed three times between  each of these....then  3 * 110   = 330 possible passes

CPhill  Aug 20, 2018
#8
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Thanks for all of your solutions!

Guest Aug 20, 2018