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Math Help - need help explaining a maths problem

  1. #1
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    need help explaining a maths problem

    hello , this is my problem : calculate (22*28*34*40)/(11*14*17*20) without using a calculator , i cant calculated without a calculator but with a calculator i get 16 ( google calculator) but how do i do this in my mind and relativly fast? is there a trick of some sort? thank you for your time.
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  2. #2
    MHF Contributor
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    There is no special trick. Just by looking and by cancellation only. Notice that 22/11 = 2
    28/14 = 2
    34/17 = 2
    40/20 = 2
    And then, 2*2*2*2 = 16.
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  3. #3
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    Hello, NiceBoy92!

    Calculate: . \frac{22\cdot28\cdot34\cdot40}{11\cdot14\cdot17\cd  ot20} .without using a calculator.
    You never taught how to reduce fractions?

    As ticbol pointed out, we have: . \frac{22}{11}\cdot\frac{28}{14}\cdot\frac{34}{17}\  cdot\frac{40}{20}

    Got it?

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  4. #4
    BORZ
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    hi

    hi every one this is my 1st time in this forum , i hope it can help me with any quetions))
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  5. #5
    Forum Admin topsquark's Avatar
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    Quote Originally Posted by BORZ View Post
    hi every one this is my 1st time in this forum , i hope it can help me with any quetions))
    Post a question and we will do our best to help you.

    But in the future, please post new comments or questions in a new thread.

    -Dan
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  6. #6
    MHF Contributor kalagota's Avatar
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    Quote Originally Posted by BORZ View Post
    hi every one this is my 1st time in this forum , i hope it can help me with any quetions))

    start a new thread if you have any inquiries.. click the upper left button which says New Thread..
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