Perms and combs (3 Viewers)

[Average Boreduser]

guys
help
pls

 

[Average Boreduser]

ans = c

 

[carrotsss]

you start by laying out the letters of the word press. then, we fill in the rest of the letters between the letters of press, so:
XPXRXEXSXSX where X are places we can put a letter.

For O, we’ve got 6 options for where to put it. If, wlog, we put it in the first spot, we end up with this for our next letter: XIXPXRXEXSXSX. So we’ve created another space for a letter. So then there are 7 options for the next letter, and likewise 8 for the next, and then 9 for the next, and 10 for the next after that, all divided by 2 factorial since there are 2 Is

this gives B, so I don’t really know why the answer would be C

 

[Average Boreduser]

you start by laying out the letters of the word press. then, we fill in the rest of the letters between the letters of press, so:
XPXRXEXSXSX where X are places we can put a letter.

For O, we’ve got 6 options for where to put it. If, wlog, we put it in the first spot, we end up with this for our next letter: XIXPXRXEXSXSX. So we’ve created another space for a letter. So then there are 7 options for the next letter, and likewise 8 for the next, and then 9 for the next, and 10 for the next after that, all divided by 2 factorial since there are 2 Is

this gives B, so I don’t really know why the answer would be C

exactly, idfk what they were trying to say here :

 

[Average Boreduser]

oh wait shit nvm the answer is b