RivalryofTroll
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- 2019
140What do the answers say?
140What do the answers say?
Is there no working for the answers?
Sorry - I'm confused as to why it's this.Suppose A and B are in a circle, and DON'T want to sit next to each other.
Then we do Total - together = 9! - 8!2!
none. no working out.Is there no working for the answers?
Yea it should defs be 8C5.none. no working out.
8C5 should be right though... dam dodgy answers...
XXXXX(AB)XXXSorry - I'm confused as to why it's this.
Oh - thanks a lotXXXXX(AB)XXX
So we have 9 elements there (we count the AB as a group since they are together), but they are in a circle, so 8!.
Now A and B can swap, so 2!.
Therefore 8!2!.
well, isn't there really just one difference to 'line' questions? (i.e. one is excluded)Oh - thanks a lot
Don't know why, but I always get confused with circles.
Thanks heaps
If you're working on a single case and doing everything at once, then multiply.Question: How do we know when to use the multiplication principle? Is there a certain way that the question is asked to hint us to use it?
10 people to choose to form 6.A committee of 6 is to be selected from 10 people of whom A and B are two. How many committees can be formed excluding A if B is included?
Doesn't the question ask to include B?10 people to choose from 6.
For this question, there are two cases:
When B is included (A must be excluded) - 8 (b/c B has to be included and A excluded) to choose from 5 ( B is already in) .'. 8C5
When B is excluded (A doesn't have to be excluded)- 9 (B is excluded) to choose from 6 (anyone else can be chosen) .'. 9C6
= 8C5+9C6 = 140
Nope, it just says IF B is included , then A is excludedDoesn't the question ask to include B?
Thanks very much.10 people to choose to form 6.
For this question, there are two cases:
When B is included (A must be excluded) - 8 (b/c B has to be included and A excluded) to choose from 5 ( B is already in) .'. 8C5
When B is excluded (A doesn't have to be excluded)- 9 (B is excluded) to choose from 6 (anyone else can be chosen) .'. 9C6
= 8C5+9C6 = 140
Nope, it just says IF B is included , then A is excluded
but B can be excluded too.
?A committee of 6 is to be selected from 10 people of whom A and B are two. How many committees can be formed excluding A if B is included?
Refer to my post about placement of commas.
English... haunts you to this day.I think it depends on how you read the question, and placement of commas.
How I interpreted it:
A committee of 6 is to be selected from 10 people of whom A and B are two. How many committees can be formed excluding A, if B is included?
What the question presumably tried to communicate
A committee of 6 is to be selected from 10 people of whom A and B are two. How many committees can be formed, excluding A if B is included?