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    Hi guys, needing some help with some nCr, nPr and factorial S1 stuff here;

    At a small branch of the Mid-West Bank, the manager has a staff of 12, consisting of 5 men and 7 women including a Mr Brown and Mrs Green. The manager receives a letter from Head Office saying that 4 of his staff are to be made redundant. In the interests of fairness the manager decides to select the 4 staff at random.
    (i) How many different selections are possible?
    (ii) How many of these selections include both Mr Brown and Mrs Green?
    (iii) Write down the probability that both Mr Brown and Mrs Green will be made redundant.

    I can do part i but part ii I have no idea how to do.

    Thanks
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    Sorry you've not had any responses about this. Are you sure you've posted in the right place? Here's a link to our subject forum which should help get you more responses if you post there.
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    (Original post by Chonty)
    Hi guys, needing some help with some nCr, nPr and factorial S1 stuff here;

    At a small branch of the Mid-West Bank, the manager has a staff of 12, consisting of 5 men and 7 women including a Mr Brown and Mrs Green. The manager receives a letter from Head Office saying that 4 of his staff are to be made redundant. In the interests of fairness the manager decides to select the 4 staff at random.
    (i) How many different selections are possible?
    (ii) How many of these selections include both Mr Brown and Mrs Green?
    (iii) Write down the probability that both Mr Brown and Mrs Green will be made redundant.

    I can do part i but part ii I have no idea how to do.

    Thanks
    for ii) you have removed Mr B & Mrs G from the list. you now have to choose 2 people from the remaining 10.
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    (Original post by the bear)
    for ii) you have removed Mr B & Mrs G from the list. you now have to choose 2 people from the remaining 10.
    Thanks
 
 
 
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