I understand the concept, but I don't understand what operation I should use to calculate the paths.

It is a (5,3) grid and the rules state: How many paths are there from (0,0) to (5,3). Paths can go UP or RIGHT, but not LEFT or DOWN.

When I look it, I see that a path from start to finish, is exactly 8 "moves".

My question is, is this the answer? or is the question asking me what are the total number of "8 paths" that I could come up with. The wording seems a bit vague

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    $\begingroup$ The question is to find the total number of "8 paths" that you could come up with. $\endgroup$ – астон вілла тереса лисбон Oct 14 '17 at 1:33
  • $\begingroup$ I have taken the liberty to shorten your title: in particular, don't use "need help" in a title. Everybody on this site could do that ... without any "added value". $\endgroup$ – Jean Marie Oct 15 '17 at 21:04

Going from $(0,0)$ to $(5,3)$ will always require 8 moves, with $5$ being right moves, and $3$ being up moves. One such example is the sequence $UUURRRRR$.

How many ways can you arrange this sequence? You can think about it as "how many ways can you change 3 $R$'s to $U$'s in the sequence $RRRRRRRR$". If you swap the different $R$'s around, will the sequence still be the same?

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  • $\begingroup$ Does that mean I should apply C(8,3) ? or possibly convert to binary and solve it that way? I've only been in this class for two weeks, so it's hard to grasp which operation I should be using $\endgroup$ – Johnny James Oct 14 '17 at 1:48
  • $\begingroup$ Yes, that's correct. You should use combinations here because the 3 $R$'s are not different from each other. $\endgroup$ – Toby Mak Oct 14 '17 at 1:49

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