Can you solve this math problem?

[CAPTAIN-OBVIOUS]

[BCRanger10]

If you go by the mathematical order of operations PEMDAS (parentheses, exponents, multiplication, division, addition, subtraction), the answer would be -1; 3 divided by 1/3 is 9, 9+1 is 10, 9-10 is -1.

[TroyDT2]

9-(3÷1/3)+1= 9-9+1 = 1

[La_isla_bonita23]

3÷1/3= 9
9-9=0
0 1= 1
The answer is 1

[La_isla_bonita23]

Thanks!!

[WindAtMyBack]

Yes, but since the order of operation is not universal, people will come up with different answers.

The person writing the equation should have used parenthesis to remove the ambiguity. Without parenthesis, only the person who wrote the equation knows the answer, since nobody else can read their mind.

Personally I would treat the fraction as a single number and divide it into 3. Then the rest is easy.

[KindManHere]

Universal as i know, since its maths, maths is same everywhere

[WindAtMyBack]

@KindManHere
For most of my life I thought it was universal also, but it turns out that it's not. People are not all taught the same order of operation.

The fraction is especially problematic. When written with a horizontal line like in the picture, I interpret that as a single number. However technically the horizontal line is division.

It could be rewritten as 3 / 1 / 3
Calculating from left to right, you would get 1

However if you view 1/3 as a single number (0.3333..) Then you would have 3 / 0.33333 = 9

I learned math before there were calculators. We always wrote both fractions and divisions using a horizontal line. Modern calculators and computers normally use single line expressions like 3/1/3. When I learned math, the horizontal line implied a bracket. A fraction is technically a division, but with the horizontal line acting as a bracket, it makes it higher priority. It's still a division, but it's higher priority than other divisions and multiplications.

But not everyone learns it this way. I think the answer is 1. Other's say the answer is 1. But the only way to get an answer of 1 is to assume the horizontal division symbol acts as a bracket.

[KindManHere]

Thanks for the reply, but Yes the answer is 1, and if they have same order, i mean if division, 3/1/3 we start from left, so its universal
Otherwise it wouldn't make sense if math was different in every country or region.

[WindAtMyBack]

@KindManHere

3/1/3 = 1.
Just that part equals 1.
If you do the entire equation from left to right:
9-3/1/3+1 = 9

For the entire equation, you only come up with1 if you bracket 1/3 like this.
9-3/[1/3] +1 = 1
The horizontal line acts as a bracket. But using inline notation ( like we are forced to use here ), then you MUST use brackets to come up with an answer of 1.

There is at least one other thing that is not universal.
12 / 2(1+3)

If you work this left to right, you get
12 / 2 = 6
6(1+3) = 24

However, when written like that, many people consider the 2 to be a factor of what's inside the parenthesis. So you would do that first.
2(1-3) = 8
12 / 8 = 1.5

Once again, not everyone agrees on how it should be done. Just because there are supposed to be universal conventions, doesn't mean everyone agrees with it or uses it.

[KindManHere]

Well in math there is a rule, first we do parenthesis, then * and / have more importance than + and -
So no matter if * and / is on left or right, they have more priority than + and -
So 9-3/1/3+1=9 yeah
9-3/[1/3] +1 = 1 because as u said we first did parenthesis part
So maths is same everywhere

[WindAtMyBack]

@KindManHere

You are missing the point. A convention is not a fixed rule that everyone uses. That's the reason why this question keeps coming up. Not everyone agrees on the convention. And kids don't all learn it the same way in school. That's because math teacher don't agree on it either.

I've seen this online over and over again. I saw the same questions before there was such a thing as online. People do not all use the same convention. Even math teachers don't agree on it.

There is a surprising amount of like that stuff in science. I'm an electronics person and worked in engineering for many years. I saw an entire engineering department erupt into a huge debate that ended up with one person getting fired. What was the big debate? Whether electricity flows from positive to negative, or negative to positive.

There is no universal convention for which direction electricity flows. So it must be stated. Math was the same way until fairly recently. In formal papers, they stated their order of operation and any other conventions and followed that throughout. It's a really bad idea to assume that everyone will use the same order of operations that you do. So it's best to state it ahead of time.

[KindManHere]

Well i thought the thing i knew right.
Anyway:D i am not scienist:)
Thanks for the detailed replies.
Since my native isn't English, i give small replies :D

[WindAtMyBack]

@KindManHere

Well, I've started teaching ESL part time. I have to be super careful with the way I say things. Native speakers don't realize how many idiomatic expressions we use. At an English speaking site like this I don't worry about it. But when teaching foreign students I have to be very careful.

Early on with a current student I was explaining "grocery store" stuff. There is a lot of math at a grocery store. A foreign person also needs to learn metric to US conversions. I was surprised at some of the differences in math. You can't assume ANYTHING.

[KindManHere]

True, like we use celcius but you use fahrenheit
There are some differences like that

[WindAtMyBack]

@KindManHere

Temperature is the only conversion I can't easily do in my head. I can get it close though.

At a grocery stores things are priced by the pound, ounce, gallon, quart, pint, etc.

[KindManHere]

I haven't heard quart and pint
But I've heard gallon, pound, ounce
But i can't do any measurement without looking at conversions on internet

[WindAtMyBack]

@kindmanhere

Quart ~= liter.
If you don't need precision that's close enough.

Pound ~= 1/2 kilogram

Yard ~= meter

Those are all easy to do in your head. The rest are a little more tricky.

[KindManHere]

I understand, thank you a lot
by the way one thing i figured it out, some people dont know the answer, when i ask if 1 litre of water or 1 litre of olive oil is heavier?
Or in frictionless environment (which is ideal environment in physic) would cotton fall down, or plane faster?
Most say plane, but it fall at same time
And sure olive oil is heavier.
But people have problem with units i guess
But i understand they dont have to like physics

[WindAtMyBack]

@KindManHere

Well, I think most people probably think of liter as both volume and weight. I had to pause myself to remember if it was volume or weight.

If you really want to throw someone off, ask them how many moles are in a liter. :)

[KindManHere]

Hahah :D
Yeah, they would stop replying lol
Chemistry i mostly forgot
As i remember we do mol calculations for gas, with 1 mol is 6.02*10^23

[WindAtMyBack]

@KindManHere

You remember the number better than I do. But it's been almost 50 years since I learned it. I haven't had a reason to remember that number.

That reminds me. I bought two avocados at the grocery store the other day. :)

[KindManHere]

Haha yeah, 50 years is a lot, so thats normal not to remember
It has been 11 years since i last studied chemistry

[MCheetah]

I've always been bad at math, so I'm just going to say three (3) with no f*cks given. Maybe I'm wrong.

[BeMuse]

Yulaw...

https://www.youtube.com/embed/Ws8JocOpkvY

[turk55]

The answer is 1. I dont like Mathemathics but this is a easy ask.

[Anonymous]

No, it's jibberish.

Learn to use brackets.

[exitseven]

there is an order of operations. division goes first. 3/ 1/3=1 so 9-1+1=9

[Opinion Owner]

No, I'm sorry, I don't even care if whoever has declared themselves king of maths has decreed that has to be the case.

I was taught to use brackets and thats what makes sense to me.

It seems like the format keeps changing so that it is incomprehensible to anyone who was taught something different.

[Opinion Owner]

@exitseven Clearly the British educational system is complete garbage.

We did the same shit over and over again for years, I never got any feedback on any of my tests and I was scoring quite well, I'm not sure exactly now how well, but I was in the top group for Maths and found the work tediously easy and yet somehow I have avoided learning this complete list of operations. I have never needed anything other than brackets.

Even if I am cynical and say that the educational system is primarily focused on teaching people to obey, that doesn't help because I don't do that either.

[Opinion Owner]

@exitseven This PEMDAS thing still doesn't make any sense to me, also you have made a mistake with your division.

When you divide by a fraction it becomes like mutliplication.

3 divided by 1/3 is 9 not 1.

So Im looking at this equation, there are no brackets, there are no exponents, there is no multiplication so it wants me to do division first, ok..

That seems to give me

9 - 9 + 1 = x

then addition, thats not helpful because if i do that then i end up with 9 - 10 which would make x -1

But everyone here is saying x = 1

So really what means is 9 + -9 +1, the 9s cancel and you are left with +1.

So i guess when i process the addition what it really wants me to do is bundle all of the positive values together, I have a plus 9 and a plus 1 and then when I subtract I get the presumably correct 10 - 9 = 1

But why does the division have an implied bracket?

shouldn't I always be able to rearrange the equation?

So multiply x by 3 and cancel the division to give me 9 - 3 + 1 = x *3?

But that definitely doesn't give me x = 1.

I am clearly missing something here because I really do not see why 3 / 1/3 is not in brackets if you want x to be equal to 1.

Am I just supposed to know that division operations have an implied bracket? Is this the same for multiplication? Presumably it would be?

[Opinion Owner]

Oh, multiplication and division are done at the same time left to right as are addition and subtraction.

That makes more sense.

I would still prefer to see a bracket around the division myself but ok, its implied. Its short hand I guess, people don't want to write something unless they have to.

Who would have thought that a mere 30 years of barely using a skill could lead to you losing it?

[exitseven]

oops you are right. 3/ 1/3 =9 and not 1. You are right.

[Static_In_The_Attic]

The answer is YES.

[NamerOfStars]

Of course- basic order of operations.

[Redstang88]

Believe it’s 1

[jennifer_bloom]

The answer is 1

[SpaceGalaxy]

N i n e t e e n

[AddylynnNightingale]

Should be 1.

[KindManHere]

1 is the answer

[Astarlessnightsky]

The Answer is 1

[Drumlin2001]

Minus 1

[Anonymous]

4...

[Dinosaursandanime65]

Is it 19?

[jimmy2]

2 I think 🤔