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    Pegs are to be placed in the four holes shown, one in each hole. The pegs come in different colours and pegs of the same colour are identical. Calculate how many different arrangements of coloured pegs in the four holes can be made using
    (i) 6 pegs, all of different colours, [1]
    (ii) 4 pegs consisting of 2 blue pegs, 1 orange peg and 1 yellow peg. [1]
    Beryl has 12 pegs consisting of 2 red, 2 blue, 2 green, 2 orange, 2 yellow and 2 black pegs. Calculate how many different arrangements of coloured pegs in the 4 holes Beryl can make using
    (iii) 4 different colours, [1]
    (iv) 3 different colours, [3]
    (v) any of her 12 pegs.

    I need help with part (iv)
    I did 6P3*4!/2!=1440.
    But the answer is wrong.
    Thanks in advance
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    (Original post by 123PC)
    Pegs are to be placed in the four holes shown, one in each hole. The pegs come in different colours and pegs of the same colour are identical. Calculate how many different arrangements of coloured pegs in the four holes can be made using
    (i) 6 pegs, all of different colours, [1]
    (ii) 4 pegs consisting of 2 blue pegs, 1 orange peg and 1 yellow peg. [1]
    Beryl has 12 pegs consisting of 2 red, 2 blue, 2 green, 2 orange, 2 yellow and 2 black pegs. Calculate how many different arrangements of coloured pegs in the 4 holes Beryl can make using
    (iii) 4 different colours, [1]
    (iv) 3 different colours, [3]
    (v) any of her 12 pegs.

    I need help with part (iv)
    I did 6P3*4!/2!=1440.
    But the answer is wrong.
    Thanks in advance
    please post some workings
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    (Original post by TeeEm)
    please post some workings
    I need help with part (iv)
    6P3*4!/2!= 1440
    which is wrong
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    bump
    (I need to look at this question today)
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    (Original post by 123PC)
    I need help with part (iv)6P3*4!/2!= 1440which is wrong


    I got 720 for this part
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    (Original post by TeeEm)
    I got 720 for this part
    That's correct. How did you solve it?
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    (Original post by 123PC)
    That's correct. How did you solve it?
    this is a variant of your question
    (I steal questions ....)
    it will help you to do yours
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    • Thread Starter
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    (Original post by TeeEm)
    this is a variant of your question
    (I steal questions ....)
    it will help you to do yours
    Thank you!
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    (Original post by 123PC)
    Thank you!
    no worries
 
 
 
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