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  1. #1
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    help(urgent)

    this is combined variation
    if q varies directly as b and inversely as c, and if q=0.2 when b=16 and c=8 find q when b=2 and c=5

    and

    if t varies directly as s and inversely as v-squared and if t= 0.1 when s=72 and v=6 find s when t=5 and v=0.2
    Last edited by machilove; January 31st 2006 at 05:47 AM.
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  2. #2
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    pls help i need it tom. I'm just new here i hope u can help me
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  3. #3
    Grand Panjandrum
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    Quote Originally Posted by machilove
    this is combined variation
    if q varies directly as b and inversely as c, and if q=0.2 when b=16 and c=8 find q when b=2 and c=5
    if q varies directly as b then there is a constant k such that:

    q=k\times b

    Now when q=0.2, b=16, so:

    0.2=k \times 16,

    so:

    k=0.2/16=1/80,

    so when b=2 we have:

    q=2/80=1/40.


    if q varies inversely as c then there is a constant m such that:

    q=m/c

    Now when q=0.2 c=8, so:

    0.2=m/8,

    so:

    m=1.6.

    Hence when c=5 q=1.6/5=8/25.

    RonL
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