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Original poster

Maths Disagreement

593 replies

TulaOfDarkWater · 04/02/2022 12:41

One person thinks the answer is 165 and the other thinks 67, who is right?

YABU - 165
YANBU - 67

Or what’s the answer if both are wrong?

Maths Disagreement
OP posts:
ThumbWitchesAbroad · 05/02/2022 14:09

[quote PugInTheHouse]@ThumbWitchesAbroad I don't think have ever used the Microsoft calculator as work on excel, that is ridiculous though Shock[/quote]
Isn't it. Doesn't help anyone with maths if the fecking calculator can't even do it right!

ThumbWitchesAbroad · 05/02/2022 16:20

@poetryandwine - so sorry, missed your post!
Yes, it may have been updated (my version is still pretty old) but certainly mine does it "wrong".

I know what you mean about the comprehension issues with "divide by half but if I were writing it as a word maths problem, I would make it much simpler:
If you have 40 cakes, and you cut all of them in half, how many halves of cake do you have?
And then add the maths question 40 ÷ ½, to show what it looks like in figures.
And then explain that to divide by fractions, you "turn them over" and multiply instead (how I was taught)
So that 40 ÷ ½ --> 40 x 2/1 = 80. Ta-dah! Grin

NumberTheory · 05/02/2022 16:26

[quote Itsalmostanaccessory]@NumberTheory

You dont need bracket in this.
You only need them if you are NOT competent. We didnt have brackets for simple things like this in high school, nor were they added when I was at uni and working through various equations because they are not needed.[/quote]
You don’t necessarily need to use brackets, juxtaposition would work better, but the line as it stands is a mess that forces you to do more work than is necessary. It’s a poor way to write maths and no one who actually wants to communicate that equation rather than trip someone up should try and convey it in that fashion

44PumpLane · 05/02/2022 16:31

It's 38

poetryandwine · 05/02/2022 17:00

No problem, @ThumbWitchesAbroad, I like your example. But you are making me hungry! Cake is one of my favourite foods

Whichcatthatcat · 05/02/2022 19:41

I still am really confused. I understand what everyone is saying about bodmas, how it works, that it was around in the 1800s or something like that, but I had genuinely never heard of it until dc were at school.
I'm sure I didn't learn it like that.
I thought the answer was 88.

And I got a b in maths o level so I can't be totally mathematically illiterate.

How can I be so wrong on something so simple yet still pass with a B?

SomeOwlsCoo · 05/02/2022 19:42

@Whichcatthatcat

I still am really confused. I understand what everyone is saying about bodmas, how it works, that it was around in the 1800s or something like that, but I had genuinely never heard of it until dc were at school. I'm sure I didn't learn it like that. I thought the answer was 88.

And I got a b in maths o level so I can't be totally mathematically illiterate.

How can I be so wrong on something so simple yet still pass with a B?

Are you sure you didn't just forget it? I'd completely forgotten it was a thing until dc learned it.
Whichcatthatcat · 05/02/2022 19:45

Unlikely that I'd have forgotten something so basic, but I guess it's a possibility.

LazySaturday · 05/02/2022 19:58

I get 35.

Top line, each shape is worth 15 but they're made up of 3 shapes in the finally line there's only 2 so that's worth 10.

Second line
23-grey shape = 8
There are 8 bananas so they're worth 1 each.

Third line
10-4bananas =6, so the clock value is the time it shows (both clocks show 3 O'Clock)

Final line
Multiplication first so 3 bananas (3) multiplied by 2 grey shapes (10) =30

Then

2 (2 O'Clock on the clock) +3(bananas)

Equals 35.

LazySaturday · 05/02/2022 20:00

But also in agreement with 38 if the 45 in the top line is number of sides, rather than allocating each shape an equal 5.

mixolydian · 05/02/2022 20:29

As many others have said, it's 38

UniversalAunt · 05/02/2022 20:37

Are we still on this?
Anybody got a new one?

modgepodge · 05/02/2022 21:51

@Whichcatthatcat

Unlikely that I'd have forgotten something so basic, but I guess it's a possibility.
Did you study any algebra though? As a few posters have said before algebra is dependent on the operations being done in the correct order. If you saw 4 + 3y would you think that was the same as 7y? If not, it suggests you did understand order of operations, even if it wasn’t called BODMAS.
Itsalmostanaccessory · 05/02/2022 22:09

@UniversalAunt

Are we still on this? Anybody got a new one?
A father is 4 times older as old as his daughter. In 20 years he will be only twice as old as his daughter. How old are the father and daughter now?

Here. Go nuts!

LazySaturday · 05/02/2022 22:15

A father is 4 times older as old as his daughter. In 20 years he will be only twice as old as his daughter. How old are the father and daughter now?

Daughter is ten and father is 40.
In 20 years time they'll be 30 and 60.

Itsalmostanaccessory · 05/02/2022 22:19

@LazySaturday

But you need to show your working using algebra!
It is very easy, but it was a puddle my 8 year old was given to get then to write word puzzles out with algebra.

EnoughOf · 05/02/2022 22:22

67

timeforteaforyouandme · 05/02/2022 22:24

35

timeforteaforyouandme · 05/02/2022 22:26

Oh yes 38 I see now

LazySaturday · 05/02/2022 22:30

[quote Itsalmostanaccessory]@LazySaturday

But you need to show your working using algebra!
It is very easy, but it was a puddle my 8 year old was given to get then to write word puzzles out with algebra.[/quote]
Wouldn't have a clue 😆
It's been a good few years since I did that!!

CasperGutman · 05/02/2022 22:31

2 + 3 + 3 × 11 = 38

ldontWanna · 05/02/2022 23:15

[quote Itsalmostanaccessory]@LazySaturday

But you need to show your working using algebra!
It is very easy, but it was a puddle my 8 year old was given to get then to write word puzzles out with algebra.[/quote]
4x + 20 = (x+20) * 2
4x + 20 = 2X + 40
2x= 20
X= 10
X is the daughter so the daughter is 10 and the dad is 40.

I should be asleep...

Wantosleep39 · 05/02/2022 23:17

It’s 38
How did you even find 165 🙈

ChildOfFriday · 05/02/2022 23:20

[quote Itsalmostanaccessory]@LazySaturday

But you need to show your working using algebra!
It is very easy, but it was a puddle my 8 year old was given to get then to write word puzzles out with algebra.[/quote]
Using algebra:

Let the father's current age = f and let the daughter's current age = d.

f = 4d
f + 20 = 2(d + 20)

Subbing the first equation into the second:
4d + 20 = 2(d + 20)
4d + 20 = 2d + 40
2d + 20 = 40
2d = 20
d =10
f = 4d = 40

Therefore, the daughter is currently 10, and the father is currently 40.

ChildOfFriday · 05/02/2022 23:21

Sorry, I was beaten to it Blush