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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:
jjkm · 12/11/2011 16:17

This reply has been deleted

Message withdrawn at poster's request.

nickelbabe · 12/11/2011 14:14

see, I do it as
5 + 5 + 5 - 5 + 5 + 5 - 5 + 5 x 0 =

brackets? no
orders? no
multiplications? yes
5x0 = 0
adding and taking away? yes.
and do them all together:
(5+5 =) 10 (+ 5 )= 15 (- 5 )= 10 (+ 5) = 15( + 5) = 20 (- 5 )= 15 (-0) = 15

the brackets are just to show you what i'm adding on or taking away.

LeBOF · 12/11/2011 14:06

I did the additions all together, then the subtractions together, as I read it aloud to myself. But I made sure I got the multiplication out of the way first.

5+5+5+5+5 =25

then take away 5 twice

=15

Thumbwitch · 12/11/2011 13:57

not how I did it. But I have accepted I got it wrong.

So: multiplications got the terminal 5 out of the way by x by 0.

Additions: 5+5+5 = 15 and then 5+5+5 = 15 again.
Grouping those together and replacing them as you suggested gave me:
15 - 15 - 5 = -5

there's a reason I never did long division - your second list of equations is pretty much illegible to me - and I still got 2 decent A levels in maths! Confused

Lougle · 12/11/2011 13:52

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

Thumbwitch, you can't have done Grin because if you did you would have done this:

Brackets? NO
Orders? NO
Multiplication? YES -> 5x0=0
5+5+5-5+5+5-5+0=?
Additions? YES -> 5+5+5=15; 5+5=10
15-5+10-5+0=?
Subtractions? YES ->15-5=10; 10-5=5
10+5+0=15

But actually, if you had followed my steps but with the correction that HazelNutt gave, you would have done something much neater:

Brackets? NO
Orders? NO
Multiplication or Division? YES ->5x0=0
5+5+5-5+5-5+0=?
Additions or Subtractions? YES ->5+5+5=15
15-5+5+5-5+0=?
15-5=10
10+5+5-5+0=?
10+5+5=20
20-5+0=?
20-5=15
15+0=15

Answer 15

nickelbabe · 12/11/2011 12:47

yes, i liked it Grin

LeBOF · 12/11/2011 12:42

Clever, isn't it?

nickelbabe · 12/11/2011 12:40

i have got it.
I did cheat a little tiny bit.

nickelbabe · 12/11/2011 12:39

i know, and part of me thinks "ooh, yes, i know that", but I'm 38 weeks pregnant and I can't be arsed to use my brain.
:(

JugglingWithGoldandMyrhh · 12/11/2011 12:38

Anyone else look at a number challenge and think "Nah , no thanks !"

  • You can tell me the answer though !
ChaosTrulyReigns · 12/11/2011 12:37

Good one.

I'll try the 8 one out on the girls.

Smile
SoupDragon · 12/11/2011 12:33

Well, yes, thats why didn't post the answer. :)

Although, given Ive solved it, it isn't difficult!

LeBOF · 12/11/2011 12:32

But maybe we should make them sweat a bit longer...

LeBOF · 12/11/2011 12:29

Go for it, Soupy!

SoupDragon · 12/11/2011 12:26

I know! I know!

nickelbabe · 12/11/2011 12:25

I don't like riddles.

LeBOF · 12/11/2011 12:19

Ummm, dunno. What do you think?

nickelbabe · 12/11/2011 12:17

is that a binary question?

LeBOF · 12/11/2011 12:16

How can you add eight 8's to get the number 1,000? (only using addition)

JugglingWithGoldandMyrhh · 12/11/2011 12:12

Those nuns are really making my head hurt Hmm Smile
What do they want with a new telly anyway ?!
I'm sure the shop assistant is up to no good and upsetting the apple cart !

Hicidycup · 12/11/2011 12:11

I live riddles Grin

JugglingWithGoldandMyrhh · 12/11/2011 12:05

Haven't read the whole thread ( Blimey 19 pages ! ) But just thinking it's crying out for brackets really isn't it ?
What sort of problem could it represent anyway ?
As a teacher (though not of maths especially) I'd say it's only purpose would be to badly illustrate why brackets are needed. Smile
If BOMDAS is right OP then so are you. So it's probably 41.

LeBOF · 12/11/2011 12:03

Grin at the salmonella

Thumbwitch · 12/11/2011 12:00

Thanks Rusty and Sherbert :)

nickelbabe · 12/11/2011 11:58

exactly.
but the way the puzzle is done, they add the £2 onto the £27 because it's been done backwards.
the puzzle makes the assumption that because the £3 has gone to the nuns, that they have paid £27 for the tv, which is correct, but as you say, the £2 didn't go to the shop.

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