1. Forum
  2. Usenet
  3. REC.GAMES.FRP.DND

  • if there are 7 power sources, and you own 4 of them

    From uglyvan@21:1/5 to All on Tue Mar 3 02:46:16 2020
    Le samedi 29 février 2020 21:16:59 UTC+1, uglyvan a écrit :
    then, how many combinations are there ?

    1 Arcane
    2 Divine
    3 Elemental
    4 Martial
    5 Primal
    6 Psionics
    7 Shadow

    1234
    1235
    1236
    1237
    1245
    1246
    1247
    1256
    1257
    1267
    1345
    1346
    1347
    1456
    1457
    1567
    2345
    2346
    2347
    2356
    2357
    2367
    2456
    2457
    2467
    2567
    3456
    3457
    3467
    3567
    4567

    ( hopefully I didn't miss any combo lol )

    the idea here is that we all share at least one power source :)

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From tkerruish@yahoo.com@21:1/5 to All on Tue Mar 3 09:14:19 2020
    To be more explicit, there are 35, which is 7 choose 4. You have 7 choices for the first power, 6 for the second, 5 for the third, and 4 for the fourth; as the ordering does not matter, you have overcounted by a factor of 24, which is 4 factorial.
    Consequently, the answer is (7×6×5×4)/(4×3×2×1) = 840/24 = 35.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)