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Thread: Four two go!

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    Four two go!

    1. A farmer knows that 20 of his hens, housed in 3 coops, will hatch 30 eggs in 18 days. How long will it take 30 hens, housed in 4 coops to hatch the same number of eggs?

    2. A car travels at a speed of 30 mph over a certain distance, and then returns over the same distance at a speed of 20 mph. What is the average speed for the total trip?

    3. Find a simple method of solving:
    6751X + 3249Y = 26751
    3249X + 6751Y = 23249

    4. A jar has 4 amoebas in it to start. Amoebas split their cells in two ( therefore doubling in size) once every minute. The jar will be completely filled in 10 minutes. How long would it take to fill the same sized jar if had 8 amoebas in it to start?
    Regards,
    Rudi

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    Re: Four two go!

    4 <span style="background-color: #FFFF00; color: #FFFF00; font-weight: bold">9min</span hide>
    Steve

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    Re: Four two go!

    2 <span style="background-color: #FFFF00; color: #FFFF00; font-weight: bold">24 mph</span hide>
    Steve

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    Re: Four two go!

    3) <span style="background-color: #FFFF00; color: #FFFF00; font-weight: bold"> I get X = 3, Y = 2. My "simple way" was to use excel matrix functions: MInvers and MMult.</span hide>

    Steve

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    Re: Four two go!

    1<span style="background-color: #FFFF00; color: #FFFF00; font-weight: bold">12 days = 18days * 20 hens/30 hens</span hide>

    Steve

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    Re: Four two go!

    Yo Steve,

    You are spot on with 2, 3, and 4. <img src=/S/thumbup.gif border=0 alt=thumbup width=15 height=15>

    If your answer for #1 is <span style="background-color: #FFFF00; color: #FFFF00; font-weight: bold">12</span hide>, then according to my answer you are incorrect!
    Regards,
    Rudi

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    Re: Four two go!

    1 <span style="background-color: #FFFF00; color: #FFFF00; font-weight: bold">The time taken for the eggs to hatch is fixed, so 18 days</span hide>

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    Re: Four two go!

    <span style="background-color: #FFFF00; color: #FFFF00; font-weight: bold"> 1. 18 days</span hide>
    Jerry

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    Re: Four two go!

    <span style="background-color: #FFFF00; color: #FFFF00; font-weight: bold">3.

    1) Add the equations to give: 10000X + 10000Y = 50000
    2) Divide by 10000 to give: X + Y = 5
    3)Subtract to give: 3502X - 3502Y = 3502
    4) Divide by 3502 to give: X - Y = 1
    5)Therefore: X = 3 and Y = 2

    </span hide>
    Jerry

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    Re: Four two go!

    Thats it Steve.

    Good Jezza...spot on too!
    Regards,
    Rudi

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