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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:
LeBOF · 09/11/2011 21:40

The only thing that confuses me there is that you aren't multiplying 2. You are multiplying 2.499999r. And that is not the same number as 2. It's a number called 2.499999r.

Or am I missing a basic maths rule? Are all two point something numbers known as two?

noblegiraffe · 09/11/2011 21:37

"since 2.5, rounded to zero decimal places always has to be handled as a 3. "

This is actually a convention rather than a hard and fast rule. 2.5 is equidistant between 2 and 3.

lazydog · 09/11/2011 21:37

"But 2.5 rounds to 2 as 2 is an even number. 3.5 would round to 4 as it is odd"

Confused Think I missed that lesson!

lazydog · 09/11/2011 21:36

Not quite the correct explanation for the 2+2=5 for large values of 2 "joke" though, since 2.5, rounded to zero decimal places always has to be handled as a 3.

It's still exactly the same theory as StrandedBear wrote, but you'd usually use 2.49 + 2.49 = 4.98, which rounds up to = 5...

HazleNutt · 09/11/2011 21:35

all who say 1, please spend some time on this page:
en.wikipedia.org/wiki/Order_of_operations

if that's too complicated, try here:

www.mathgoodies.com/lessons/vol7/order_operations.html

TeamDamon · 09/11/2011 21:35

Am ROFL-ing at the fact that even though numerous maths teachers have stated with absolute certainty that the answer is 41 and explained why, there are still posters turning up to the thread and saying with equal certainty that it's 1 Grin

noblegiraffe · 09/11/2011 21:35

Stranded, you could use 2.49 recurring, which is equal to 2.5 but would round down to 2 :)

Tiggles · 09/11/2011 21:34

But 2.5 rounds to 2 as 2 is an even number. 3.5 would round to 4 as it is odd, so I guess by that theory 3+3 could equal 7.

The answer is definitely 41
40 + 40*0 + 1
40 + 0 +1
41

wahwahwah · 09/11/2011 21:32

it's 1

LeBOF · 09/11/2011 21:31

That's interesting Grin

StrandedBear · 09/11/2011 21:28

This reply has been deleted

Message withdrawn at poster's request.

crockydoodle · 09/11/2011 21:28

The answer is 41 - I have maths A Level

winnybella · 09/11/2011 21:23

Yes, I meant if there were brackets, say (40+40)x0+1 it would go: 80x0+1=1

So of course it isn't always multiplication first, not if there are brackets like in the example above.

But in OP's case it is 41. 100%

GreenEyesandNiceHam · 09/11/2011 21:21

How interesting?

Nothing like a maths thread to bring out the inner twat Grin

HazleNutt · 09/11/2011 21:19

Why should there be brackets? You multiply first. You really do. Or at least should.

And then it's 41.

winnybella · 09/11/2011 21:17

Of course you do the multiplication first Shock Brackets or no brackets.

It is 41. 40+0+1=41.

DunRovin · 09/11/2011 21:17

How can 2+2=5?

The same way the sum below equals 41?

Wallace · 09/11/2011 21:17

cross-posted Grin

OhYouBadBadkitten · 09/11/2011 21:15

gnight all

coastgirl · 09/11/2011 21:15

For everyone worried about the standard of maths education, note there are a lot of us who are getting it right and quite articulately explaining why, so it can't be all that dire. I think a more pernicious attitude is the idea that everything is up for debate, which maths isn't.

Wallace · 09/11/2011 21:15

That is why I like maths :)

StrandedBear · 09/11/2011 21:15

This reply has been deleted

Message withdrawn at poster's request.

SalVadorDavi · 09/11/2011 21:14

41 obviously

OhYouBadBadkitten · 09/11/2011 21:14

it really is 41, its a written down sum not a set of instructions to be taken from left to right.
honestly.

ok, time for a belated Grand Designs :)

glencoco · 09/11/2011 21:14

It is 41, I say so and so does my incredibly clever 14 year old who has an a* in maths GCSE so I trust her!

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