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    A four-digit number is to be formed from digits 1,2,3 and 4.
    (a) How many odd numbers greater than 3000 can be formed if repetition is not allowed?

    thanks
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    (Original post by nerdygeek123)
    A four-digit number is to be formed from digits 1,2,3 and 4.
    (a) How many odd numbers greater than 3000 can be formed if repetition is not allowed?

    thanks
    What have you tried?
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    (Original post by joostan)
    What have you tried?
    I don't know what I need to do for this question
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    (Original post by nerdygeek123)
    I don't know what I need to do for this question
    What seems to be the problem?
    There's no real need for fancy tricks - the number of cases is sufficiently small you can probably just write them down.
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    (Original post by nerdygeek123)
    A four-digit number is to be formed from digits 1,2,3 and 4.
    (a) How many odd numbers greater than 3000 can be formed if repetition is not allowed?

    thanks
    Greater than 3000 -> first digit must be 3 or 4.
    Odd -> last digit must be 1 or 3.
    So: 3241, 3421, 4231, 4321, 4123, 4213 = 6 numbers.
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    (Original post by HapaxOromenon)
    Greater than 3000 -> first digit must be 3 or 4.
    Odd -> last digit must be 1 or 3.
    So: 3241, 3421, 4231, 4321, 4123, 4213 = 6 numbers.
    this really helped thanks
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    I'm teaching myself S1 this year instead of doing m2 ... does anyone have an OCR S1 advanced maths essentials textbook/revision guide thingy ... it has a cd and a book ... I their guide with CD for M1 and it was amazing (went from U to an A on my own!) ... I know they do it but its not available to buy presumably because this is the last year of this spec? PLEASE LET ME KNOW I REALLY NEED ONE and would love to take it off your hands if you're finished
 
 
 
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