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Math Help - permuatation help

  1. #1
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    permuatation help

    hwo many arrangements of ISOSCELES can be done if no 2 letters of clsss can be together , i have tried many times but never could get the answer the answer is 240 please help me
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  2. #2
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    Re: permuatation help

    Hello, righteous818!

    How many arrangements of ISOSCELES can be done if no 2 letters of CLSSS can be together?

    We have 9 spaces to fill.

    . . \_\_\;\square\;\_\_\;\square\;\_\_\;\square\;\_\_ \;\square\;\_\_


    Place \{E,E,I,O\} in the four boxes.
    . . There are: \frac{4!}{2!} = 12 ways.

    Place \{C,L,S,S,S\} in the five blanks.
    . . There are: \frac{5!}{3!} = 20 ways.


    Therefore, there are:. 12\cdot20 \,=\,240 arrangements.
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