Anonymous
Anonymous asked in Science & MathematicsMathematics · 8 years ago

How would I list all permutations of five objects a,b,c,d, and e taken three at a time without replacement?

2 Answers

Relevance
  • Anonymous
    8 years ago
    Best Answer

    I'd suggest trying to list them in alphabetical order. There are 60 possibilities, as shown below.

    Personally, I used an Excel macro and some filtering and sorting

    abc

    abd

    abe

    acb

    acd

    ace

    adb

    adc

    ade

    aeb

    aec

    aed

    bac

    bad

    bae

    bca

    bcd

    bce

    bda

    bdc

    bde

    bea

    bec

    bed

    cab

    cad

    cae

    cba

    cbd

    cbe

    cda

    cdb

    cde

    cea

    ceb

    ced

    dab

    dac

    dae

    dba

    dbc

    dbe

    dca

    dcb

    dce

    dea

    deb

    dec

    eab

    eac

    ead

    eba

    ebc

    ebd

    eca

    ecb

    ecd

    eda

    edb

    edc

  • 8 years ago

    There are five objects a,b,c,d,e

    Three are taken at a time.

    Number of permutations = n! / (n-r)!................[ without any repetitions]

    = 5! / (5-3)!

    = 5! / 2!

    = 5 x 4 x 3 x 2 x 1 / 2 x 1

    = 60

    HOpe this helped.

Still have questions? Get your answers by asking now.