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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:
GrimmaTheNome · 10/11/2011 10:13

Pacific - the first time I read that one I misread one of the minuses tooSmile

SoupDragon · 10/11/2011 10:12

It was Grimma's test sum.

I can believe I went to all the hassle of finding the calculator on my Air only for it to get something smile wrong. They can programme a phone to tell jokes but not a properly functioning calculator... clearly the phone programmers are better than the Macbook ones.

PacificDogwood · 10/11/2011 10:11

Oh, FFS, history repeating itself for me: I always, always in school made errors relating to Not Reading the Frigging Question right. For goodness sake, you'd think 25 years later I've learnt

Of course it is 15.
Why oh why did I just not see that second minus?? After looking at that questions repeatedly??

RustyBear · 10/11/2011 10:08

iphone calculator gets it right! On both simple and scientific.

On the other hand, the 'Calculator for iPad HD' which I got from the app store (the ipad didn't come with a calculator) makes it 81 in landscape mode and 41 in portrait mode, which is ridiculous. I think I will be looking for a new calculator app for the ipad...
(It does get Soupy's test sum right though)

SoupDragon · 10/11/2011 09:53

Mac Air calculator 1+2x3 = 9. [sigh]

GrimmaTheNome · 10/11/2011 09:48

About calculators - evidently some do just evaluate left to right. If you're on a windows machine, try its Calculator. First in the default view
1 + 2 * 3

Then switch it to 'scientific' or programmer and do the same.
Obviously the latter two are correct!

SoupDragon · 10/11/2011 09:46

I'd never heard of BODMAS until recently. We just learnt the rules with no acronym.

SoupDragon · 10/11/2011 09:45

"to make it 1 it would have to read 40+(40xO)+1"

No, to make it 1 it would have to read (40+40) x 0 +1

Pascha · 10/11/2011 09:41

Its taken me minutes and minutes breaking that down on paper and in my head Totem and Grimma. My brain hurts Blush And its the calculator on my computer which is brand new this month.

I am ashamed to say I somehow got C at GCSE maths in 1993 and I have never heard of BODMAS. I went to a grammar school.

(I still don't really get it)

TotemPole · 10/11/2011 09:36

0 is a strange answer. You'd have to add everything up then multiply by 0 last.

Even if you don't know BODMAS, going left to right and getting 1 as the answer makes more sense.

If you go right to left, or assume different bracketing, the answer is 80.

(40 + 40) x (0 + 1) = 80

legspinner · 10/11/2011 09:35

to make it 1 it would have to read 40+(40xO)+1

legspinner · 10/11/2011 09:34

41 using BODMAS; multiply first

MyNameIsLola · 10/11/2011 09:28

I also say 41 and agree BODMAS applies here.

CatsRule · 10/11/2011 09:26

I also think it's 41 applying the multipy first rule.

If I can remember correctly there would need to be brackets in place to make it 1.

GrimmaTheNome · 10/11/2011 09:24

41 - but it's a bad question because of the multiply by 0 bit
Its a perfectly reasonable question. Its at the waaay simple end of the sort of thing anyone who writes software has to deal with all the time.

Now, if there was a divide by zero, that's a different matter.

bruffin · 10/11/2011 09:23

I remember working out brackets first, but not the multiplication before addition and subtraction.

StrandedBear · 10/11/2011 09:22

This reply has been deleted

Message withdrawn at poster's request.

GrimmaTheNome · 10/11/2011 09:21

Pascha - is your calculator the sort where you can type in that whole line at once or do you have to do it in stages? If the latter, its implicitly bracketing.
If the former - its a duff calculator!

TotemPole · 10/11/2011 09:21

5 + 5 + 5 - 5 + 5 + 5 - 5 + 5 x 0 =

Pascha, BODMAS, there are no brackets and no order(powers/exponentials), no division.

The first operation is multiply. So multiply the last 5 X 0 = 0

Then add.
There are 5 +5s and 1 +0 = 25 + 0 = 25
Then take away the 2 -5s. 25-10 =15

Pakdooik · 10/11/2011 09:21

41 - but it's a bad question because of the multiply by 0 bit

Chocolategirl3 · 10/11/2011 09:20

everyone in my office is thick too Blush

GrimmaTheNome · 10/11/2011 09:19

Bruffin - I don't remember the BODMAS acronym but I'm quite sure I learned the same rules of precedence at school (O -levels 77, A levels 79)

The rules have evolved over time, but the one at the nub of the OP is centuries old. Here is a bit of a discussion .

As to early calculators - well, the first was the Sinclair which used Reverse Polish notation and I really don't think we want to go there! Grin

StrandedBear · 10/11/2011 09:19

This reply has been deleted

Message withdrawn at poster's request.

TotemPole · 10/11/2011 09:16

bruffin, I did o level in the 80s and we learned BODMAS then.

Pascha · 10/11/2011 09:14

i dont get the one with all the fives Confused. My calculator says 0.