HP 10BII Combination Permutation - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html) +--- Forum: General Forum (/forum-4.html) +--- Thread: HP 10BII Combination Permutation (/thread-17235.html) HP 10BII Combination Permutation - Gamo - 07-11-2021 05:29 AM HP 10BII+ got this functions but not for the HP 10BII HP 10BII User Manual doesn't provide the way to calculate this and here is my attempt. Formulas: Permutation: nPr = n! ÷ [ (n - r)! ] Combination: nCr = n! ÷ [ r! x (n - r)! ] Example: 6P3 6 [-] 3 [=] [n!] [÷] 6 [n!] [SWAP] [=] display answer 120 6C3 6 [-] 3 [=] [n!] [x] 3 [n!] [=] [÷] 6 [n!] [SWAP] [=] display answer 20 Remark: The Factorial Function limit is up to 253! = 5.17 E499 Gamo 7/2021 RE: HP 10BII Combination Permutation - Gamo - 07-21-2021 08:10 AM Update key steps for both the "Combination and Permutation" by the use of the memory key [→M] Example: ►A child has a set of toy blocks with the 26 letters of the alphabet each appearing once. How many different three-letter permutation ( 26P3 ) can be made with these blocks? 26 [→M] [-] 3 [=] display 23.00 [n!] display 2.59 E22 [÷] [RM] [n!] display 4.03 E26 [SWAP] [=] display answer 15,600.00 ►A manager wants to choose a committee of three people from the seven engineers working for him. In how many different ways cn the committee be selected? ( 7C3 ) 7 [→M] [-] 3 [=] display 4.00 [n!] display 24.00 [x] 3 [n!] [=] display 144.00 [÷] [RM] [n!] display 5,040.00 [SWAP] [=] display answer 35.00 Gamo