MATHS S1 HELP NEEDED - URGENT

[SarcasticNerd]

Hi. I'm prolly screwed in Maths S1 paper tomorrow. However, people please help me out a little.

When do you use nPr and nCr formula? I always mix them up so if somebody could please help me with that. And if somebody have any last minute revision notes of S1 for me, I'll really appreciate it. And any other tips related to S1 will be highly appreciated. Thanks.

 

[Binyamine]

The video Solutions for June 2009 9709/62 :: https://www.youtube.com/playlist?list=PLOueJSLH9a-Ngx2v4rR3vQ_FZIoSzqzie

Or you can have all solution from http://anagnorisis.usefedora.com/courses/s1-bundle-var2