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Is it correct that seven and five is thirteen or seven and five are thirteen?

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What is Correct - solution

Of course, adding seven to five makes twelve and not thirteen.

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• 4 weeks later...
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no really any 1 who can add knows that u ****

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Just a little catch. Maybe there is someone who fell for it.

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I don't really think it's a question entirely about math. Wouldn't the word "makes" or "equals" need to be in there to make you add? or "the sum of seven and five is..."

The words is and are imply a state of being which numbers by themselves do not have. To me the only way this statement makes sense is to say that seven and five are numbers of some kind of nouns. I guess they would be pronouns in the statement. And 13 is another sort of designation.

Apples and oranges are fruit.

That being said I didn't see it as asking me to add the numbers together. I saw them as seperate objects. Maybe 13 year old students (wouldn't that be about right for the age group of this sort of question?)

Seven and five are thirteen.

Seven is thirteen

Five is thirteen

Seven and five equal twelve...

The sum of seven and five is twelve...

Also, another point. The information given by the question supports my logic. I just made up my own story as to how either statement could be correct. To me it asks which statement is correct. Not if 7+5=13.

If I had a teacher ask my kid this, then tell him he was wrong because he answered "ARE" I would be pretty pissed.

This question is probably why half of people that speak english say "apples IS good" instead of "apples ARE good"

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To warpath:

Good point. You can have a look at the other puzzles as well and correct the terrible English since I am not a native speaker.

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To warpath:

Good point. I have amended the puzzle accordingly. You can have a look at the other puzzles as well and correct the terrible English since I am not a native speaker.

I was asked this question as a youth, and you did nothing wrong in the wording. It just a trick in more than one way. I eventually was able to explain why I said the correct statement was seven and five are thirteen to my teacher. I am pretty sure my teacher worded it exacttly like you did before, maybe it had different numbers. After some embarassment due to being made fun of by other kids.

I just found it to be a grammar question and not a math one. An english teacher asked me this.

I think it needs to be worded with is and are like it was before.

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A a linguist I have to say that you got this one wrong. Just because something is not true does not make it incorrect grammar and vice versa:

The sky [is | are] red.

The answer is "is" despite the statement being incorrect.

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• 3 weeks later...

tricky tricky! have to use that one on my math teacher! hehehe good one!

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• 2 weeks later...

the answer is neither because seven plus five is twelve. and correct english is "seven and five is twelve." well, even if it isn't "correct," that is the colloquial way of saying it. why? because we say seven plus five IS twelve, so why would you say seven and five are twelve? it just sounds weird.

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I must reiterate that seven plus five is thirteen are correct - even though the sentance is false.

In enlgish there is a difference between true and correct.

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The reason we would say that seven and five are something and not seven and five is something is simply because the "and" in between them makes us assume that they are grouped together and we wouldn't say the apple and orange is fruit. We would say the apple and orange Are fruit. Since the wording of this puzzle is at question we assume it's an English based question so Math based rules wouldn't apply to it. Now, if the question had "solve this math question" before it, then we would have to assume math rules apply and wouldn't worry about the English rules and we'd immediately call the question wrong do the adding error.

So, either we make the question more specific or we make our answer more broad. We could ask them to solve the math problem, like I've stated before, or we can answer the question by saying "Seven and Five ARE Thirteen".

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this is a classic riddle, where the premise is that as the math is incorrect, neither statement is correct. please don't make it a grammar problem...

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The reason we would say that seven and five are something and not seven and five is something is simply because the "and" in between them makes us assume that they are grouped together and we wouldn't say the apple and orange is fruit. We would say the apple and orange Are fruit. Since the wording of this puzzle is at question we assume it's an English based question so Math based rules wouldn't apply to it. Now, if the question had "solve this math question" before it, then we would have to assume math rules apply and wouldn't worry about the English rules and we'd immediately call the question wrong do the adding error.

So, either we make the question more specific or we make our answer more broad. We could ask them to solve the math problem, like I've stated before, or we can answer the question by saying "Seven and Five ARE Thirteen".

This is exactly what I have been saying.

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• 2 weeks later...

The original Puzzle / Riddle that I heard was:

'which is the correct Statement, 'The yolk of an egg is white' or 'the yolk of an egg are white''

The answer is niether statement is correct as the yolk of an egg is yellow.

This removes some of the arguements that a couple of the more pedantic responses replied with.

The question is not which is grammatically correct, it is which complete statement is correct. Hence the answer.

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the adding of the word statement changes a lot. Without it, due to choice between to logically similar statements that differ only in grammar, it must be assumed that "which is correct" is asking regarding grammar. "Which is a correct statement?" removes this implication and thus resolves the difficulty that we had. Maybe the original question should be altered.

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• 2 weeks later...

The answer to "Is it correct that seven and five is thirteen or seven and five are thirteen?" is, without any doubt, both. "seven and five is thirteen" is mathematically correct and "seven and five are thirteen" is grammatically correct.

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um 7 +5 = 12; not 13 Mythx

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neither is correct 7+5=12

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Why would it ask for correct mathematical statement when the answer is clearly wrong?

If it is a grammar question about math then 7 and 5 IS 13 because 7+5 is one mathematical expression.

If it is a grammar question of items then 7 and 5 ARE 13 because 7 and 5 are considered different items and AND is not use as operator but as conjunction.

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Comperr, I must disappoint you. 7 + 5 = 13, is most certainly correct. It is correct when performed in base-9. I know this sounds very pedantic, but it just is.

Conversions from base-x to base-10

13 in base-10: 1 * 10^1 + 3 * 10^0 = 10 + 3 = 13

13 in base-9: 1 * 9^1 + 3 * 9^0 = 9 + 3 = 12

There we go, the correct answer.

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This is true. It is not something I thought of because as a programmer "I only work with 2, 8 , 10, and 16.

But that is true

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I thought of it because of the joke "6 * 9 = 42", this joke is from The Hitchhiker's Guide to the Galaxy. It's performed in base-13.

right - yeah.

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• 4 weeks later...
A a linguist I have to say that you got this one wrong. Just because something is not true does not make it incorrect grammar and vice versa:

The sky [is | are] red.

The answer is "is" despite the statement being incorrect.

Grammatical correctness does not imply correctness as a whole. The nature of a brain teaser is that it challenges us to look at many angles. Thus, regardless of the grammatical correctness, the content of the statement must also be correct for the entire statement to be correct.

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