90÷9(8-3x2)?

Please explain why you get your answer, as I used BODMAS/BIDMAS but get both 5 and 20, depending on how i treat the bracket. I just need to know the rule on why it would be 5 and not 20? if 5 is correct

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  • 1 year ago

    Always start with brackets.

    (8-3x2)

    Since multiplication comes before subtraction, you do 3x2 which equals 6.

    Now you’re left with (8-6) which equals 2.

    Now you have 90/9(2)

    Since multiplication and division are left, you now work left to right.

    90/9=10

    10(2)=20

    Therefore the answer is 20.

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  • 1 year ago

    90/ 9(8-3*2)

    =90/9(8-6) (multiplication will come first in brackets)

    =90/9 of 2

    = 90/18 ( we do the action of of before division according to the rule of BODMAS)

    =5

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  • 1 year ago

    90÷9(8-3x2) 1st do the multiplication inside the parentheses which is 3 x 2

    =90 ÷ 9(8 - 6) then get the difference between 8 and the product of (3x2) which is 6

    =90 ÷ 9(2) multiply 9 times the difference between (8 and 6)

    =10(2). get the quotient of 90 and 9 then multiply it by 2.

    = 20 answer//

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  • Jim
    Lv 7
    1 year ago

    90÷9(8-3x2), if you spread it out it's easier to see what's going on:

    90 ÷ 9 * (8-3x2)

    = 10 * 2 <<<< using left to right rule!

    = 20

    no question!

    ===

    WA agrees...

    Attachment image
    Source(s): Most people forget that (BOMDAS) PEMDAS groups M&D together as equals, AND you do them Left to Right!!!! Maybe we should make it PEDMAS (BODMAS)! Pink Elephants Do Mash and Stomp! would be a better memory aid, especially since division is the only problem child!
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  • PEMDAS stands for Parentheses, Exponents, Multiply, Divide (multiplying and dividing are done from left to right, so if division is on the left of multiplying it can be done first), Add, and Subtract (add and subtract done left to right)

    Your problem is 90/9(8-3x2).

    There is a problem in parentheses! We'll do that first.

    Multiplication is done before subtraction, so 3*2=6. Then, 8-6=2. Parentheses done.

    the 9(2) we've got with is multiplication. There's division (90/9), so we'll do that first.

    90/9=10

    10*2 (the * can be used for multiplication) is 20.

    Hope I answered your question! Math can be tricky, and it's good to reach out for help!

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  • 1 year ago

    90÷9(8-3x2) => 90÷9(8-6) => 90÷9x2 => 90÷18 => 5. There is no answer to this problem. The problem is ambiguous and nobody that writes expressions like this in their professional life should ever be an engineer. They would get somebody killed.

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  • 1 year ago

    90 ÷ 9(8 - 3 x 2)

    = 10(8 - 3 x 2)

    = 10(2)

    = 20

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  • ted s
    Lv 7
    1 year ago

    as typed you have [ 90 ] / [ 9 (8 - 3 x²) ] = 10 / (8 - 3 x²)...ie 90 divided by nine sets of ( 8 - 3 x²)

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  • 1 year ago

    In the stepsps of BODMAS/BIDMAS/PEMDAS, parentheses/brackets must be cleared before anything else; here, since you have a subtraction and multiplication within the parentheses, you multiply and/or divide, then you add and/or subtract -- in both cases, start with the leftmost operation in each pair and treat all multiplications and divisions on the same tier as each other, and treat all additions and subtractions on the same tier as each other. So:

    90 / 9(8 - 3 * 2)

    = 90 / 9(8 - 6)

    = 90 / 9 * 2

    You would think the answer is 5. BUT IT'S NOT.

    The 9 was NOT enclosed within parentheses, so you CAN'T multiply 9 * 2 first; you'd have to divide 90 / 9 first since the leftmost operation is division. Do that, then multiply the quotient by 2 -- the correct answer as you have typed it is 20.

    If this were 90 / (9(8 - 3 * 2)), THIS is 5.

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  • 1 year ago

    If that is how the problem was presented to you, then the question-setter is in the wrong. It is vital that expressions are presented in a clear and unambiguous way. Maths is about precision and clarity, and ambiguity is incompetence.

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