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Original poster

40+40x0+1 ?

539 replies

minimuffy · 09/11/2011 19:48

40 + 40 x 0 + 1 =

A- 1
B- 41
c- 0

I say its B-41 as you need to multiply then add. (from what i remember of standard grade maths the acroymym BOMDAS- brackets off, multiply, divide, add, subtract)

DH says its 1.

please tell he's wrong!

OP posts:
PoppadumPreach · 09/11/2011 20:34

I agree atyourcervix. It would be far more sensible to have wee men inside computers with semaphore flags.

coastgirl · 09/11/2011 20:34

40 + 40 x 0 + 1 =

Do the multiplication first - 40 x 0 = 0

Then the additions - so you have 40 + 0 + 1 = 41.

Multiplication always comes before addition unless there are brackets directing you otherwise. If it were (40 + 40) x 0 + 1, for example, it would be 81.

LeBOF · 09/11/2011 20:34

It doesn't help that I keep having to scroll up to hold the sum in my mind. I have real trouble reading numbers- I can't look at train timetables etc without them just vanishing when I look at the station name Grin. it makes stuff like this, with it at the top of the page really difficult. I just can't hold onto numbers in my brain, if that makes sense?

MorningPurples · 09/11/2011 20:33

some pupils are taught 'o' for pOwers instead of 'i' for indices.

We were taught BEDMAS (Brackets, Exponents, Divide/Multiply, Add/Subtract), but they don't seem to use the word exponents anymore.

trixymalixy · 09/11/2011 20:33

order of operations

meala · 09/11/2011 20:33

BODMAS (or BOMDAS) means

Brackets
Of (or over, eg fractions 1/2 of 12 etc)
Divide
Multiply
Add
Subtract

and is the order you should do calculations in.

So, if there are brackets you do anything inside the brackets first. If there are no brackets, move on to the next items on the list.

In this case, move on to multiplication (as there are no fractions to carry out). So do calculation 40 x 0 = 0.

Then add everything together to get answer.

Hope that helps Smile

(PS - I am also a maths teacher, it is a common mistake to do calculations in the wrong order) Here is another description.

TeamDamon · 09/11/2011 20:32

DH - PhD in maths and maths teacher - says 41. He also said 'bodmas'.

Iggly · 09/11/2011 20:31

You multiply the two numbers immediately either side of the multiply sign.

OhYouBadBadkitten · 09/11/2011 20:31

you do the two numbers that are next to the multiply sign, them and them alone!

coastgirl · 09/11/2011 20:31

It's 41 and if you say 1 you're DOING IT WRONG.

LeBOF · 09/11/2011 20:31

Can you apply that to the sum for me and talk me through it, please, Kitten, or anyone?

saggarmakersbottomknocker · 09/11/2011 20:31

We drew a pencil line under the ones we used lots.

OhYouBadBadkitten · 09/11/2011 20:30

if there are no brackets then you go on to the next bit. There are no indices either (and no division) so the next operation you do is multiplication.

LeBOF · 09/11/2011 20:30

Yes, I get that you multiply first- but which bit do you multiply, and why?

Original poster
minimuffy · 09/11/2011 20:29

yey!

OP posts:
LeBOF · 09/11/2011 20:29

I know where I'd like to insert them...

rhondajean · 09/11/2011 20:29

Did it on 3 calculators - 2 say 41, one says 1!!!!!

Sigh...

Adversecamber · 09/11/2011 20:28

This reply has been deleted

Message withdrawn at poster's request.

LeBOF · 09/11/2011 20:28

But there are no brackets, so where do we mentally insert them, please? I'd really like to understand this, and I don't yet.

Original poster
minimuffy · 09/11/2011 20:28

you still have to multiply first then add, with or without brackets!

OP posts:
meala · 09/11/2011 20:27

Definitely 41.

Always multiply or divide first so 40 x 0 = 0
Then add or subtract 40 + 0 + 1 = 41

(I have a phd in maths, you are correct and your DH is mistaken)

AtYourCervix · 09/11/2011 20:27

why would anyone want to turn letters into numbers? why is an a not just an a.

like fuckinglightbiulbs and plugs. much more complicated than it ever needs to be.

smartyparts · 09/11/2011 20:27

My 13 yr old says it's 1 (because there are no brackets).

Is he right.

Wallace · 09/11/2011 20:26

41

LifeOfKate · 09/11/2011 20:25

Am I the only one who thought the answer was 80? Blush
I am SHIT at maths tbf :o