Ask your own question, for FREE!
Mathematics 13 Online
OpenStudy (anonymous):

@Directrix You're always really helpful, =) could you please help me with this problem? Thirteen people are entered in a race. If there are no ties, in how many ways can the first three places be awarded? a. 1716 b. 858 c. 39 d. 1684

Directrix (directrix):

Order matters because there are lst, 2nd, and 3rd place awards. @bumblebee3 How many different people could possible win lst place? Please post that and then we'll do 2nd place.

OpenStudy (anonymous):

Okay, 13 different people could win 1st place. : )

Directrix (directrix):

Yes. One of them wins. Next question: How many different people are left for contenders for 2nd place? Post and we'll do 3rd place and then put the problem together for a final answer.

OpenStudy (anonymous):

12 different people can get 2nd place.

OpenStudy (anonymous):

And 11 different people could get 3rd place. : )

Directrix (directrix):

Okay. Using the Fundamental (Basic) counting Principle as given on the attachment, there are 13*12*11 ways for 3 of 13 people to win lst, 2nd, and 3rd places. So what does that multiply out to be. @bumblebee3 And, you can study a bit more about the counting principle here: http://www.mathsisfun.com/data/basic-counting-principle.html

OpenStudy (anonymous):

Okay, so I got 13*12*11= 1716. Thanks for the website link!

Directrix (directrix):

1716 is what I got.

OpenStudy (anonymous):

Great! Thank you so much! =)

OpenStudy (anonymous):

Also, for this problem, I have a quick question! Does order matter? Because if it does, then the answer is 42, if it doesn't matter then the answer is 21. Thank you so much! A committee is to consist of two members. If there are seven people available to serve on the committee, how many different committees can be formed?

Directrix (directrix):

If you're on the committee, you are on the committee. Order does not matter. Think about it this way: I'm choosing two people out of seven to give a free iDevice. Does it matter whether a person is chosen first or second? No, because both would get the gift. So, run the combination formula through C(7,2) --> Seven, choose two.

OpenStudy (anonymous):

Alright, thank you so much for all your help! =)

Directrix (directrix):

You are welcome. P.S. I got 21.

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!