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What's 2 x 3 + 4 x 1 + 6 x 0 ?

(1001 Posts)
mirai Thu 10-Oct-13 04:37:05

I work (abroad) in a school and I've just observed a lesson with this sum written on the blackboard.

The teacher gave an answer but I'm not sure it's the right one... So I want to see what MN thinks!!

Even using BODMAS the answer is 0. Anything multipled by zero equals zero.

PrincessRomy Thu 10-Oct-13 05:25:54

But you do the adding after the multiplying. So it's only the 6 that is multiplied by 0, not the rest of the equation.

Flossie82 Thu 10-Oct-13 05:26:48

Yes, anything multiplied by Zero is zero

But only the 6 is being multiplied by zero

The resulting zero is then added

Adding zero does not equal zero

Thu 10-Oct-13 05:29:54

If it was intended to be one of those sums where you set it out a stage at a time and give a "running total" at each stage, so each new stage is meant to apply to the entire previous running total, not just the number before it, iyswim, then I can see how you would get 0. Otherwise, when taken as a single sum, 10.

Not sure I'm making myself very clear though [bleary eyes].

fuzzpig Thu 10-Oct-13 05:31:44

I'd be worried too. This teacher is obviously assuming you do all calculations in the order they are written if there's no brackets. But the point of BODMAS is to avoid unnecessary brackets, they should be able to see the priority (ie multiplying) without the brackets!

Sorry that probably made no sense (I'm really not supposed to be awake )

Thu 10-Oct-13 05:32:35

Definitely 10. Teacher is an idiot.

GuybrushThreepwoodMP Thu 10-Oct-13 05:39:35

10.
As others say, the 0 is only to be multiplied by the 6 just as the 2 is multiplied by the 3.
Could also be written: (3x2)+(4x1)+(6x0)=10

The other answer would be given like this :
(3x2+4x1+6)x0=0
But that is a completely different sum.
I'm not sure where some of you have got 16 from unless you think 6x0 is 6?

I'm coming back to this thread when I'm more awake (with my pencil and paper to work this out properly). I'm now very confused.

Curious as to what age was the class?

Ah, I see.
Thank you GuybrushThreepwoodMP.

TotemPole Thu 10-Oct-13 06:14:29

10

tumbletumble Thu 10-Oct-13 06:16:24

10

Thu 10-Oct-13 06:23:40

Definitely 10. I'd be appalled if someone was teaching that to my DC!

Thu 10-Oct-13 06:26:56

Ten. No question.

meditrina Thu 10-Oct-13 06:28:04

10.

And a teacher who doesn't know BODMAS isn't fit to teach maths.

10

You can google BODMAS calculator, if you are uncertain.

Thu 10-Oct-13 06:39:23

Come on, of course it's 10! Ffs I would complain about the teacher!

shelley72 Thu 10-Oct-13 06:44:59

10. How can it not be?

thistlelicker Thu 10-Oct-13 06:45:39

I must be the only one who got 16 then ! Maths wasn't my thing tho and it clearly shows !! Ha

coffeewineandchocolate Thu 10-Oct-13 06:50:50

10

Pachacuti Thu 10-Oct-13 06:52:22

10, because of BODMAS.

kelda Thu 10-Oct-13 06:52:50

10.

What country are you in?

SusieSusieSheep Thu 10-Oct-13 06:55:12

I really hope the teacher is aware that maths is not their forte.

DSJamesHathaway Thu 10-Oct-13 06:55:35

10. I'm surprised at the number of people getting it wrong.

EndoplasmicReticulum Thu 10-Oct-13 07:03:46

I think 10 too.

Degustibusnonestdisputandem Thu 10-Oct-13 07:12:26

Yep 10 also, because of BODMAS

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