6^2 ÷ 2(3) + 4 = ? Mathematician Explains The Correct Answer

This math problem went viral on Twitter and I've seen a lot of debate about the answer. I explain why one interpretation is considered correct.

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[rhondaweber]

I consulted my son, who is a math major on this issue and he said, " It's a poorly written equation due to the ambiguity of it. No mathematician would write an equation like this." Problem solved!

[tavismillard]

Another interpretation of "I saw the man with binoculars" is "I cut the man in half using a pair of binoculars to do so". Just saying.

[michaeltanner]

This is where for division you’d just put it in a fraction, it clears up all ambiguity

[UteChewb]

This is why I always use parentheses. Life is too short to argue over precedence.

[francis]

If it can to be "interpreted", it is not a legitimate arithmetical expression, it is simply incomplete or lazy.

[lolz]

Math is a language. If you can't write it properly, don't expect to be understood.

[Zer-zzxc]

No mathematician divides like this, this is one of the reasons why every one use fraction when they are in higher maths.

[noone]

The moment when you can make out the apparently critical precedence rules, but fail at calculating 18*3...

[aaron]

This shit is why I prefer fraction lines...

[NightyCore]

For me the correct one is 10. You can not just get rid of the brackets as you see fit in the given equation, nor add them when you want. The website, got rid of brackets around 3 which, as soon as it did that, changed the equation. Google on the other hand as far as i saw just added more so it can separate everything, which again shouldnt be done. The solution for me is 10 and i am sticking with it :D My reason and opinion: It would be like this: 6^2 *2(3) + 4. If i follow google i can add brackets here: (6^2/(2*3)) +4 which should equal 10. And for the website one it just put fractions and deleted the brackets which you shouldn't do, since you didn't solve the bracket. At least thats how i was thaught. So im sticking with 10 :D

[JKiler]

I've been using math at least long enough to know that it doesn't take nearly as much effort to make the answer to an equation apparent as it does to make it obscure.

[johnspathonis]

I ran into this very type of problem a few days ago. Excel interprets it as 58. If you want the 2 and 3 together then in Excel you have to bracket around them forcing them to multiply first before dividing.

[chunchan]

is nobody going to address the fact that there's no equal sign in this "equation" making it an expression?

[AlexAegisOfficial]

It's not a amthematical problem. its a syntax problem. It's just written very ugly. It should be: 6^2 / (2 * 3) + 4 = 10 or (6^2 / 2) * 3 +4 = 58

[elimartin]

This goes against everything I was taught, PEMDAS

P - parentheses
E - exponents
M - multiplication
D - division
A - addition
S - subtraction

[shinobi]

If you properly use Pemdas, you would get 58. The parentheses first only applies to the inside of the parentheses so if there isn't anything to solve in the parentheses then it just acts like a normal number and if there is a number next to the parentheses where that would act like a multiply. The second is step in Pemdas is exponents. Third is multiply or divide, if even though multiply comes before divide in the Pemdas acronym they have the same priority and it would go left to right. This means you would do the divide by 2 before the multiply by 3. The forth and final step is add and subtract, the same priority rule on multiply and divide also applies to addition and subtraction.

[SteveMcRae]

6^2 ÷ 2(3) + 4 = 36 ÷ 2(3) + 4 = 18(3) + 4 = 54 + 4 = 58. Why do people insist on using their own rules in math rather than simply by going by established standard order of operations. You can't assume that 2(3) is part of the "same term" as terms are separated by addition and subtraction signs, not implicit multiplication operators.

[raymendez]

Correct answer, wrong method. There is no exception to the rule, parenthesis are always first. In this case it will be:

6^2 / 2 x (3) + 4
6^2 / 2 x 3 + 4
36 / 2 x 3 + 4
18 x 3 + 4
54 + 4
58

The only difference with the correct answer but wrong method on the video is I did parenthesis first. And that's how it should be.

[Memorie]

In terms of algebra, if you have an equation like 5 / 2a, you would consider 2a a single integer rather than 2 x a, therefore you would solve 2a first. This is why I believe 10 makes more sense in an equation like this.

[SadieGoetsch]

"PEMDAS" or whatever other shortcut you have learned states that with mulitpliplication and division, or addition and subtraction, you do whatever comes first when reading left to right.

P-Parentheses = There aren't any to solve, as the (3) has been solved
E-Exponents = 6^2 = 36
M/D- Muliplication/Division = 36/2 = 18, 18*3 = 54
A/S-Addition/Subtraction= 54+4 = 58

58.