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Math Help - proportional reasoning

  1. #1
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    proportional reasoning

    On the number line above, a and b represent distances between numbers as shown. If the ratio of a to b is 1 to 6, what is the value of b ?
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  2. #2
    No one in Particular VonNemo19's Avatar
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    Quote Originally Posted by aeroflix View Post
    On the number line above, a and b represent distances between numbers as shown. If the ratio of a to b is 1 to 6, what is the value of b ?
    1 is to six as k is to k^2.

    Set up and solve.
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  3. #3
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    36?
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  4. #4
    No one in Particular VonNemo19's Avatar
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    Quote Originally Posted by aeroflix View Post
    36?
    Yes, that is k^2...k^2-k=b, right?
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  5. #5
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    but according to here

    SAT Skills Insight

    check skill 8 exanple. the answer is 42. what the? their wrong
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  6. #6
    No one in Particular VonNemo19's Avatar
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    Quote Originally Posted by aeroflix View Post
    but according to here

    SAT Skills Insight

    check skill 8 exanple. the answer is 42. what the? their wrong
    42=k+k^2...so I would say that they are wrong, but I've been known to be wrong myself at times.

    It's elementary

    \frac{1}{6}=\frac{k}{k^2}
    \frac{1}{6}=\frac{1}{k}
    k=6,k^2=36...

    Maybe Im not seeing things right.
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  7. #7
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    yah , they say b is 42. and we say b is 36. did u check the website?
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  8. #8
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    Quote Originally Posted by aeroflix View Post
    On the number line above, a and b represent distances between numbers as shown. If the ratio of a to b is 1 to 6, what is the value of b ?
    \frac{a}{b} = \frac{k}{k^2-k}

    \frac{1}{6} = \frac{1}{k-1}

    k-1 = 6

    k = 7

    b = k^2 - k = 49 - 7
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