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Math Help - I can't seem to get the correct answer to this fraction, what am I doing wrong?

  1. #1
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    I can't seem to get the correct answer to this fraction, what am I doing wrong?

    This is the sum with which I'm having trouble:

    8 3 1/5 = ?

    This is how I've tried to do it:

    8/1 16/5

    Then I have found the reciprocal of 8/1:

    1/8

    Therefore,

    1/8 X 16/5 = 16/40

    BUT
    the answer is not 16/40 but 2 1/2.

    40/16 would be 2 1/2.

    What do I need to do?

    Thanks
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  2. #2
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    Re: I can't seem to get the correct answer to this fraction, what am I doing wrong?

    Quote Originally Posted by popopopop View Post
    This is the sum with which I'm having trouble:

    8 3 1/5 = ?

    This is how I've tried to do it:

    8/1 16/5

    Then I have found the reciprocal of 8/1:

    1/8

    Therefore,

    1/8 X 16/5 = 16/40

    BUT
    the answer is not 16/40 but 2 1/2.

    40/16 would be 2 1/2.

    What do I need to do?

    Thanks
    It's the SECOND fraction you need to invert, not the first...
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  3. #3
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    Re: I can't seem to get the correct answer to this fraction, what am I doing wrong?

    Quote Originally Posted by popopopop View Post
    This is the sum with which I'm having trouble:

    8 3 1/5 = ?

    This is how I've tried to do it:

    8/1 16/5

    Then I have found the reciprocal of 8/1:

    1/8

    Therefore,

    1/8 X 16/5 = 16/40

    BUT
    the answer is not 16/40 but 2 1/2.

    40/16 would be 2 1/2.

    What do I need to do?

    Thanks
    You need to flip the fraction you're dividing by - in this case 16/5
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  4. #4
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    Re: I can't seem to get the correct answer to this fraction, what am I doing wrong?

    You have it backwards.
    \frac{a}{b}\div\frac{c}{d} = \frac{a}{b} \times \frac{d}{c}
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  5. #5
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    Re: I can't seem to get the correct answer to this fraction, what am I doing wrong?

    Thank you, I thought that might be why.

    By the way, hello to all.
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