My Math Forum 2 question in permutations and Combination

 Algebra Pre-Algebra and Basic Algebra Math Forum

 February 25th, 2010, 04:04 AM #1 Senior Member   Joined: Oct 2009 Posts: 895 Thanks: 1 2 question in permutations and Combination 1 ) There are 10 teams in a league. If each team is to play every other team exactly once, A ) How many games must be scheduled? B ) How many games must be on each team? [color=#BF0000] A ) 10C9 = 10 B ) 10C1 = 10[/color] 2 )_A catering service offers 8 appetizers, 10 main courses and 7 desserts. A Chairperson is to select 3 appetizers, 4 main courses and 2 desserts for A dinner. How many way can this be done? [color=#BF0000]Here in this question we use C or P and why?[/color]
 February 25th, 2010, 12:20 PM #2 Global Moderator   Joined: May 2007 Posts: 6,704 Thanks: 669 Re: 2 question in permutations and Combination Your first question answers look completely wrong. A) is 45 and B) is 9.
February 26th, 2010, 03:54 AM   #3
Member

Joined: Feb 2010

Posts: 51
Thanks: 0

Re: 2 question in permutations and Combination

Quote:
 Originally Posted by mathman Your first question answers look completely wrong. A) is 45 and B) is 9.
mathman is right ( in fact he seldom be wrong, lol)

answer for 1A is 10C2 = 45
There are 10 teams and in each match, there will be 2 teams playing with each other.
The reason to choose 'C' but NOT 'P' is because the order is not important. For example, Team A playing with Team B is just the same as Team B playing with Team A.
When we use 'P', the order is important, for example,the arrangement of AB is not the same as BA.

For part b, since the question states that 'There are 10 teams in a league. If each team is to play every other team exactly once', that already shows that there are 9 matches each team is going to play (**Team A can't play with Team A in a competition, right?)

Well, I don't know whether it is the correct explanation because I just learnt it last month and that's just the way my maths teacher taught us. Hope that it helps

 March 4th, 2010, 08:19 AM #4 Newbie   Joined: Mar 2010 Posts: 2 Thanks: 0 Re: 2 question in permutations and Combination 2 more que's.... Q1) Calculate the number of ways in which the letters of the word TRIANGLES can be arranged if no two vowels may come together. Q2) How many 7-digit numbers can be formed from the digits 0,1,2,2,3,3,3 assuming that a number can't start with 0 ?????????
 March 4th, 2010, 09:08 AM #5 Global Moderator   Joined: Dec 2006 Posts: 20,370 Thanks: 2007 Hi maria1 Please create a new topic for your question instead of adding it to an existing topic.

### Did Catering services can apply permutations?

Click on a term to search for related topics.
 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post EvanJ Advanced Statistics 1 February 17th, 2014 05:09 PM jasonbing Advanced Statistics 1 December 13th, 2011 07:42 PM r-soy Algebra 1 March 4th, 2010 02:35 AM david79 Applied Math 3 September 26th, 2009 05:17 PM EternalSummer247 Advanced Statistics 2 August 17th, 2007 05:03 PM

 Contact - Home - Forums - Cryptocurrency Forum - Top