6÷2(1+2) = ?

PHDs in mathematics say it's ambiguous...

Hobby jogger with degrees in sports science and weed say it's not...

I wonder who I'll side with...

Lets Run Snobs Have No Self Awareness.. wrote:

PHDs in mathematics say it's ambiguous...

Hobby jogger with degrees in sports science and weed say it's not...

I wonder who I'll side with...

I am numb to the assertions of morans thanks to COVID threads. But somehow I thought this basal level of nuance would be understandable to LRC trolls.

Fool me twice….

Lead Foil Hat XVI wrote:

2600 bro wrote:

The point of math notation is to express ideas clearly.

The fact this is interpreted so ambiguously shows it's just written poorly. Use fraction notation...

But following traditional 5th grade algebra and PE(MD)(AS), the answer is 9. Mult/Div and Add/Sub have the same priority and you just move left to right. So this is just 3 * 3 = 9.

Finally you are correct about something. Seattle Prattle seems to have forgotten basic elementary school math rules

Yes, you are right that I did get it wrong, at least as per the excellent You Tube video i looked up to get an explanation, which is both informative and convincing.

As i said before: "Ok, I looked it up and there is a very good You Tube video on it. I won't spoil it.

Pretty neat."

You don't have to have Bekele's leg muscles transplanted in your brain to work out that the answer is 1

the answers 1

This post is truly an indicator of how different the education systems are around the world.

The answers here are indicators of how different the education systems are around the world.

2600 bro wrote:

Lenny Leonard wrote:

This is the correct answer.

It's not ambiguous. When you write 2(1+2), that is different than 2 * (1+2). It is intentionally written as 2(1+2) to show that it is one number, not strictly an operational shorthand.

The fact we have 4 pages here shows it is not as unambiguous as you think. Write clearly for your audience. It's not that hard.

I do, however, disagree that implied multiplication takes precedence over other operations. It's not functional evaluation.

It is written clearly. If someone solves it incorrectly, it is a reading error, not a writing error.

2(1+2) is a monomial. It is equal to 6. It doesn't matter what else happens anywhere else in the equation; 2(1+2) is always and forever to be 6.

That is unambiguous.

The correct answer is 1.

While PEDMAS places multiplication before division, 2(1+2) is a term resolved first by either:

1. applying distributive law, simplifying the problem to 6 / (2 + 4) -> 6 /6 =1

OR

2. performing the parentheses operation, then resolving the term; 6 / 2(3) -> 6/6 = 1

This is clearer when equations and expressions are written with division being over/under a separating line.

seattle prattle wrote:

Lead Foil Hat XVI wrote:

Finally you are correct about something. Seattle Prattle seems to have forgotten basic elementary school math rules

Yes, you are right that I did get it wrong, at least as per the excellent You Tube video i looked up to get an explanation, which is both informative and convincing.

As i said before: "Ok, I looked it up and there is a very good You Tube video on it. I won't spoil it.

Pretty neat."

You get your knowledge of reality from Youtube?

Lenny Leonard wrote:

2600 bro wrote:

The fact we have 4 pages here shows it is not as unambiguous as you think. Write clearly for your audience. It's not that hard.

I do, however, disagree that implied multiplication takes precedence over other operations. It's not functional evaluation.

It is written clearly. If someone solves it incorrectly, it is a reading error, not a writing error.

2(1+2) is a monomial. It is equal to 6. It doesn't matter what else happens anywhere else in the equation; 2(1+2) is always and forever to be 6.

That is unambiguous.

2(1+2) is equivalent in most systems to 2*3 is not a monomial. We took very different math classes it seems.

Perhaps, there are some systems where the convention to evaluate operator-less implied multiplication before other operators but that is not a universal rule. The responses in this thread alone should show you that.

If you are only one that abides by a "rule" it's a not rule - you are just out of touch.

6÷2(1+2) =?

As there is no mathematical operator between 2 and (1+2) it is 3 (3) and it means nothing.

The operator is missing.

Lenny Leonard wrote:

math is easy wrote:

the answer is 1.

2(1+2) is one number. You can't separate the 2 from the parenthesis.

This is the correct answer.

It's not ambiguous. When you write 2(1+2), that is different than 2 * (1+2). It is intentionally written as 2(1+2) to show that it is one number, not strictly an operational shorthand.

No, this is not true.

2600 bro wrote:

The only people who are wrong are those who assert others are wrong.

You are wrong.

Imagine thinking that the use of a single ÷ means (for some reason) that every term to the right of that symbol is suddenly part of the divisor? What rule of mathematics is that? Ya'll crazy.

Nope.

6/2(1+2)

6/2(3)

3(3)

9

9.

The multiplication doesn't come first. Multiplication and division are treated equally and read left to right.

Funny to see so much arguing over nothing.

Open a spreadsheet, type in a formula like this without enclosing the entire denominator in parentheses, and see if it interprets it correctly, or even as a valid expression at all. That's how it's been for decades.

Following up on what linguistics-poster said, these expressions are all shorthand language, in which division and multiplication are different expressions of the same thing. 6 /2 means the exact same thing as 6 x 2^-1. Because multiplication is associative in the set of real numbers, it makes no difference which operation is performed first.

It only SEEMS to matter if you choose to use a division symbol instead and neglect to make clear what the denominator is. The given expression is, by convention, equivalent to

6 x 1/2 x (1 + 2)

That is how it's evaluated in just about any real-world context. Type 6 / 2 * 3 into a spreadsheet or calculator and see for yourself. It's what it means, so if you were taught different, you were taught wrong.

ardour wrote:

The answers here are indicators of how different the education systems are around the world.

In the United States, the most important thing in education is each student having his /her own opinions. And students are told every student's opinion is valuable.

In some other countries, education is about teaching some basic, objective facts.