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Thread: Mow the lawn

  1. #1
    Silver Lounger kweaver's Avatar
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    Mow the lawn

    Ethan can mow three lawns in five hours.
    Stefan can mow four lawns in seven hours.
    If they work together, how fast can they mow two lawns?

    [show your work]

  2. #2
    4 Star Lounger
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    105 minutes...Stefan is the slower of the two and takes 105 minutes per lawn.

  3. #3
    Silver Lounger kweaver's Avatar
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    He's slower but they're working together. How did you arrive at 105 min.?

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    Ethan can mow 3/5 lawn per hour (0.6).
    Stefan can mow 4/7 lawn per hour (0.57).
    If they are both mowing the same lawn we add the times to get 1.17 lawns per hour, so less than 2 hours for both lawns.

    cheers, Paul

  5. #5
    5 Star Lounger RussB's Avatar
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    It all depends on how big the two lawns are, what shape they are or how many turns are needed.
    Do you "Believe"? Do you vote? Please Read:
    LEARN something today so you can TEACH something tomorrow.
    DETAIL in your question promotes DETAIL in my answer.
    Dominus Vobiscum <))>(

  6. #6
    Super Moderator BATcher's Avatar
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    I make it 102.4-ish minutes, 60 * 2 / (3/5 + 4/7).

    What a boring life these lawn arrangers lead!
    Are all La Jolla lawns equally-sized?!
    BATcher

    If it goes right, nobody remembers;
    if it goes wrong, nobody forgets.

  7. #7
    Silver Lounger kweaver's Avatar
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    RussB: no it doesn't.

    BATcher: we have brown lawns if any because of the lack of water here!

    LAWNS.jpg

  8. #8
    Gold Lounger Maudibe's Avatar
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    Darn!!! I waited 4 1/2 months for a new post and I didn't even get a chance to have a stab at it! Maybe some time in 2016

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