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1 hour ago, The Hallucinating Goose said:

If you work out this maths problem, what answer do you get? 

8 - 8 x 8 + 8

 

I don't know if maths is taught differently these days but apparently the answer I get is not correct. 8-64-88

8-64-8=-56-8 =-48

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7 hours ago, The Hallucinating Goose said:

Right, 8 is what I get from doing it exactly the same way you did it. Like yourself, I was never very good at maths. 

Can someone please explain to me, as simply as possible, why the answer is -48?

Maximus mentioned BIDMAS above. Also known as BODMAS. It helps you remember which order to do the separate calculations in. Brackets, operations or indices (any squaring or cubing etc), division, multiplication, addition, subtraction. 

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27 minutes ago, glossop saint said:

Maximus mentioned BIDMAS above. Also known as BODMAS. It helps you remember which order to do the separate calculations in. Brackets, operations or indices (any squaring or cubing etc), division, multiplication, addition, subtraction. 

I was always taught you did the calculations in brackets if there is any and then do the rest of the problem in order as it is written. So if the 8 x 8 was in brackets you would get -48 but it isn't in brackets here so, like I say, I was taught you just did the separate calculations in the order they are written. 

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1 hour ago, The Hallucinating Goose said:

I was always taught you did the calculations in brackets if there is any and then do the rest of the problem in order as it is written. So if the 8 x 8 was in brackets you would get -48 but it isn't in brackets here so, like I say, I was taught you just did the separate calculations in the order they are written. 

This is where i stand. No brackets, no order of calculations required

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1 hour ago, The Hallucinating Goose said:

I was always taught you did the calculations in brackets if there is any and then do the rest of the problem in order as it is written. So if the 8 x 8 was in brackets you would get -48 but it isn't in brackets here so, like I say, I was taught you just did the separate calculations in the order they are written. The 

The brackets are implied. Confirmation from TonyXIII, please.

 

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The algebraic rules of precedence are:

1. Brackets 
2. Exponents  
3. Multiplication
4. Division
5. Addition
6. Subtraction.

BEMDAS

Computer programmers who do not understand maths cause confusion as they sometimes write programs that do a straight left to right order of calculation.

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11 hours ago, The Hallucinating Goose said:

If you work out this maths problem, what answer do you get? 

8 - 8 x 8 + 8

 

I don't know if maths is taught differently these days but apparently the answer I get is not correct. 

Asked a lot of people  (of a certain age) , they all answered 8 .....so it seems maths is taught differently these days .

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8 minutes ago, The Hallucinating Goose said:

How do you know where the brackets are implied? 

Drummed into me in maths lessons. 😀😀

Actually, Padge explained it perfectly in his post. In the absence of parentheses and exponents, you evaluate the multiplication. 

Edited by JohnM
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Just tried it on my calculator on my phone.

When I did, 8-8×8+8 I got -48

However doing,  8-8=, then ×8=, then +8=   got 8.

The calculator assuming brackets around 8x8

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6 hours ago, The Hallucinating Goose said:

How do you know where the brackets are implied? 

If you see x or * or / or ÷ then brackets are implied around the numbers either side of the operator when they are not there.

1+2*3 therefore is 1+(2*3)=7 and 1-2÷4 therefore is 1-(2÷4)=0.5

Simple calculators work on a straight (incorrect) left to right operation, scientific calculators usually follow the algebraic convention.

Edited by Padge
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35 minutes ago, unapologetic pedant said:

Treated as the left side of an algebraic equation where a is 4, it becomes 2a - 2a × 2a + 2a.

This would be written 2a(2a - 2a) + 2a.

Clearly, the first term equals zero, leaving 2a. Hence, the answer is 8.

No it would be 2a -(2a*2a)+2a Or 8-(8*8)+8 the first operator is * thus it becomes 8-64+8  next 8-64 = -56 giving -56+8 which = -48.

Answer is -48

Note Multiplication and Division have equal weighting as do addition and subtraction, once the multiplication is done the maths becomes a straight left to right calculation.

Edited by Padge
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11 minutes ago, Padge said:

Multiplication and Division have equal weighting as do addition and subtraction, once the multiplication is done the maths becomes a straight left to right calculation.

 

8 hours ago, Padge said:

The algebraic rules of precedence are:

1. Brackets 
2. Exponents  
3. Multiplication
4. Division
5. Addition
6. Subtraction.

BEMDAS

Computer programmers who do not understand maths cause confusion as they sometimes write programs that do a straight left to right order of calculation.

So is your 1 to 6 order wrong? Shouldn't it be 1, 2 3=, 3=, 5=, 5=

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8 hours ago, ivans82 said:

Asked a lot of people  (of a certain age) , they all answered 8 .....so it seems maths is taught differently these days .

It’s not just taught differently if you put it in that order into a calculator it does come out as -48. 

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