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  1. #1
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    Default Maths Question

    I've been trying to figure this out for about an hour.. but to no avail.

    In words:
    Three boys ran in a race. Their total time was 24 minutes.
    Bill ran 3 minutes quicker than Peter.
    Michael ran 3 times quicker than Bill.
    Find the race times of each boy.

    tl;dr:
    x + 3 = y
    y * 3 = z
    x + y + z = 24



    From what I've gotten:

    x + (x+3) + 3 (x+3) = 24

    5x + 12 = 24
    x = 12 / 5
    y = 12 / 5 + 3
    y = 27 / 5
    z = y x 3
    z = 81/5

    Therefore

    x = 2.4
    y = 5.4
    z = 16.2


    Is this right? I've asked several people, but they've gotten different answers.

    inb4doyourhomeworkyourself

    Thanks.

  2. #2
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    Quote Originally Posted by woshiibreak View Post
    I've been trying to figure this out for about an hour.. but to no avail.

    In words:
    Three boys ran in a race. Their total time was 24 minutes.
    Bill ran 3 minutes quicker than Peter.
    Michael ran 3 times quicker than Bill.
    Find the race times of each boy.

    tl;dr:
    x + 3 = y
    y * 3 = z
    x + y + z = 24



    From what I've gotten:

    x + (x+3) + 3 (x+3) = 24

    5x + 12 = 24
    x = 12 / 5
    y = 12 / 5 + 3
    y = 27 / 5
    z = y x 3
    z = 81/5

    Therefore

    x = 2.4
    y = 5.4
    z = 16.2


    Is this right? I've asked several people, but they've gotten different answers.

    inb4doyourhomeworkyourself

    Thanks.
    Maybe you should go back and ask your buddies at PC World!

    THREAD LOCKED CAUSE WOSHII IS A B!TCH. how could you, woshii, how could you...

  3. #3
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    Quote Originally Posted by power_gamer_6 View Post
    Maybe you should go back and ask your buddies at PC World!

    THREAD LOCKED CAUSE WOSHII IS A B!TCH. how could you, woshii, how could you...

    I saw that too. I am disappoint.

  4. #4
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    B, p, m

    b=p-3 (bill ran 3 mins faster than peter, so peter's time minus 3 equals bill's time)
    -->p=b+3 (solve for p)
    m=b/3 (michael was 3 times quicker than bill, so if you take bill's time and divide it by 3 you get michael's)

    b+p+m=24 (the three equal 24)

    b+(b+3)+(b/3)=24 (solve for b)
    3b/3 + (3b+9)/3 + b/3 = 72/3 (find common denominator)
    (4b + 3b + 9)/3 = 72/3 (combine)
    7b+9=72 (multiply both sides by 3 to get rid of fraction)
    7b=63

    b=9
    m=3
    p=12

    b+m+p = 24

  5. #5
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    Quote Originally Posted by Paladuck View Post
    B, p, m

    b=p-3 (bill ran 3 mins faster than peter, so peter's time minus 3 equals bill's time)
    -->p=b+3 (solve for p)
    m=b/3 (michael was 3 times quicker than bill, so if you take bill's time and divide it by 3 you get michael's)

    b+p+m=24 (the three equal 24)

    b+(b+3)+(b/3)=24 (solve for b)
    3b/3 + (3b+9)/3 + b/3 = 72/3 (find common denominator)
    (4b + 3b + 9)/3 = 72/3 (combine)
    7b+9=72 (multiply both sides by 3 to get rid of fraction)
    7b=63

    b=9
    m=3
    p=12

    b+m+p = 24
    Moa got this :l

  6. #6
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    Bill ran 3 minutes quicker means his time was 3 minutes shorter than Peter's.

    That's where your x + 3 = y is wrong.

  7. #7
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    Well my name is Michael and I'm pretty fast so this makes sense I guess.

    But yeah it's right.

    Quote Originally Posted by power_gamer_6 View Post
    Maybe you should go back and ask your buddies at PC World!

    THREAD LOCKED CAUSE WOSHII IS A B!TCH. how could you, woshii, how could you...
    u have no power here, sir.

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