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    Hi all, I'm having trouble with the following question.

    'A Maths group consists of 10 students, 6 of the students are boys. One of the girls is called Maria, and two of the boys are called Peter and David.
    Four students are selected at random.

    (i) Calculate the total number of ways they can be chosen
    (ii)How many ways include Maria
    (iii)How many ways include Peter and David'

    For part (i), I did 10C4 which gives 210 possible ways of choosing the four students.

    On part (ii), I am struggling with. Could anyone give me any pointers about where to begin with this question

    Any help is greatly appreciated
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    (Original post by mp1998)
    For part (i), I did 10C4 which gives 210 possible ways of choosing the four students.

    On part (ii), I am struggling with. Could anyone give me any pointers about where to begin with this question
    Consider one of those 210 selections. What is the probability that Maria is in it?
 
 
 
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Updated: March 13, 2016

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