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[Core] Please help combinatorics question

Please help combinatorics question

I'm not quite sure how to approach both (c)(i) and (c)(ii). Can someone please give a hint?
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7c)i)
You always start by picking any 6 points out of the 10. That's easy, 10C6.

Now focus on these 6 points, how exactly can you divide them into 2 groups of 3, such that the two triangles won't overlap?
If 3 are on "one side", the other 3 on "the other side", right?
Now try to be a bit more specific about it, and count the number of ways of dividing them into "one side" and "another side".
There should be just 3 ways.

Thus, the answer is 10C6 (picking 6 points out of 10) x (and) 3 (3 ways of dividing 6 points into 2 pairs of 3 such that the triangles won't overlap).

Note: I wrote it weirdly, because I'm a big proponent of, for combinatorics questions, interpreting each number/symbol in words, to see if what you're saying makes sense.

7c)ii)
And overlap... the pair of triangles either overlaps, or it doesn't, so...

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Thanks

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