Funatic Maths

Counting

  • Written on
    - Paper 1

    Question 10

    In a certain country, 1010-digit telephone numbers with the following format were introduced:
    Image
    Digits may be repeated.
    10.110.1 How many possible 1010-digit telephone numbers could be formed? (2)(2)
    10.210.2 Certain restrictions were placed on the groups of digits:
    • Area code: must be 33 digits and the first digit can NOT be 00 or 11
    • Exchange code: must be 33 digits and the first and second digits can NOT be 00 or 11
    • Number: must be 44 digits and the first digit MUST be a 00 or 11
    10.2.1\quad 10.2.1 How many valid 1010-digit telephone numbers could be formed by applying the given restrictions? (3)(3)
    10.2.2\quad 10.2.2 Determine the probability that any randomly chosen 1010-digit telephone number would be a valid phone number. (2)(2)
    [7]\textbf{[7]}
  • Written on
    - Paper 1

    Question 11

    11.111.1 Events AA and BB are independent. P(A)=0,4P(A)=0,4 and P(B)=0,25P(B)=0,25.
    11.1.1\quad 11.1.1 Represent the given information on a Venn diagram. Indicate on the Venn diagram the probabilities associated with each region. (3)(3)
    11.1.2\quad 11.1.2 Determine P(A  or  NOT  B)P(A\; or\; NOT\; B). (2)(2)
    11.211.2 Motors Incorporated manufacture cars with 55 different body styles, 44 different interior colours and 66 different exterior colours, as indicated in the table below.
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    • The interior colour of the car must NOT be the same as the exterior colour.
    • Motors Incorporated wants to display one of each possible variation of its car in their showroom. The showroom has a floor space of 500m2500\, m^2 and each car requires a floor space of 5m25\, m^2.
    Is this display possible? Justify your answer with the necessary calculations. (6)(6)
    [11]\textbf{[11]}