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Question:

anr
anr
Student
Community / Jr. College

5/6·1/2+2/3÷4/3

How do I solve this problem?

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Posted by anr on Tuesday September 22, 2009 at 1:59 PM and tagged with math, pre algebra hw..

Answers:


  1. marilynn07 Teacher
    High School - 9th Grade

    eNotes Editor

    You would set this problem up as an order of operations problem.

    First you eliminate parentheses

    Second you eliminate exponents

    Third you multiply and divide in order from left to right

    Fourth you add and subtract in order from left to right.

     

    Here is a sentence to help you remember what to do first.

    Please         excuse        my dear                Aunt Sally.

    (parentheses) exponents multiply and divide add and subtract

     

    5/6*1/2+2/3/4/3

    reorder terms (when dividing fractions use the reciprocal of the second fraction and multiply them)

    5/6*1/2+2/3*3/4

    multiply fractions (you could cross multiply)

    5/12+6/12

    add fractions (be sure that the denominator for both fractions is the same, and add the numerators)

    11/12 answer

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    Posted by marilynn07 on Tuesday September 22, 2009 at 6:01 PM

  2. neela
    neela Teacher
    Graduate School

    eNotes Editor

    5/6.1/2+2/3 '/. 4/3

    Reading: 5 diveded by 6multiplied by1 plus divided by 2 divided by3 divideb4 divided by 3.

    The operation   / or '/. are dividing operation.

    The operation  . is multiplication.

    The operation + is addtion.

    Procedure: In this case, division and multplication are of equal priority. So do them in first come first serve basis.The addition is last.

    Therefrore,

    In 5/6*1/2+2/3'/.4/3, we take 5/6*1/2 first

    5/6*1/2=5/12  +                                           (1).

    Now we take 2/3'/.4/3:

    2/3'/.4=(2/3)/4=2/12=1/6.

    The result (1/6) divided by 3=(1/6)/3=1/18        (2)

    Now do the addtion + between the result flagged at (1) and (2):

    5/12+1/18. make them equivalent fractions with a common denominator 36:

    5/12=5*3/(12*3) =15/36

    1/18=1*2/(18*2)=2/36

    So.5/12+1/18=15/36+2/36 =17/36=0.47222....

    If you still have doubt check this with a scientific calculator, or a Ms exel  and feed the data in the same fashion you posed here and check the result. They are programmed and order of operations are taken care of in them.

    Most people may confuse with second term after plus + here while simplification:

    2/3'/.4/3 is equivalent to 2divided by 3divided by4divided by3

    Successive divisions are here. No parantesis. / and '/. are the same operations and no priority arises as they look in different shape. There is no freedom to pick any two successive numbers in the middle or last. So you have to effect the divsion from left only , 'On first come first serve basis'.

    Therefore 2/3'/.4/3=2/3/4/3 does not give us the freedom to choose the last 4/3 first. So,2/3'/.4/3= 2/3/4/3 = 2/3 first and the result/4. Then divide by3. So,2/3'/.4/3=0.666.../4/3=0.166666/3=0.05555...... or

    2/3'/.4/3=2/12/3=2/12/3=2/36=1/18

    Hope this helps.

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    Posted by neela on Tuesday September 22, 2009 at 7:45 PM