This is bizarre. The info provided in the question was that Marty ate more than Luis, the question was how would that be possible given that Marty ate 4/6 of his while Luis ate 5/6 of his. The answer the kid wrote (Marty's pizza was bigger than Luis') is the only possible correct answer.

The grader is asserting that the information given in the question was wrong and that "actually it was Luis who ate more pizza"--even though it stated as a premise that "Marty ate more". How are you supposed to give a correct answer on a test if you are expected to accept one premise (proportion of pizzas eaten) while disregarding another premise (Marty ate more than Luis)? How do you decide which part to disregard? Would they have accepted the answer, "Luis actually only ate 3/6 of his pizza, not 5/6)"? Wouldn't that be just as valid an answer as "Marty actually didn't eat more than Luis"?

The title of this post is disappointing. The given answer is sound and it seems safe to assume it was arrived at by thinking mathematically.

that kid passes my class with honors

the teacher is a moron

When I was in elementary, my teacher said that "Lutetia" was how the Romans called the city of Liege. As an avid reader of Asterix comics, I knew this isn't true and corrected her and said it was the Roman name of Paris. She insisted that it is Liege. Anyway, the next day, she came back to class and said that she looked it up and that I was indeed correct and Lutetia referred to Paris and gave me a chocolate bar and told me to keep reading comics. Good teacher.

I suspect many commenters are missing the point, the student's response can only be the correct and expected answer to this question. Teacher has it wrong.

The teacher is fucking stupid. The question says Marty ate more, that is not only possible it is a given.

This is genuinely baffling. What was that teacher on.

Teachers that don't accept an unexpected but true answer are not teaching. The test taker had a correct take, one of the pizzas could be bigger than the other. It was not specified in the question. I am so glad I am out of school

Ah, a teacher that does not comprehend the barometer

Two other right answers:

• Luis' pizza is at least smaller than Marty's (which is basically the same answer as the kid's)
• Marty ate someone else's pizza besides his own

And, for funsies:

• Luis' pizza is 50% crust, so it doesn't fully count as pizza
• Luis doesn't like pizza and actually fed the dog while nobody was looking
• Marty is many years older than Luis, therefore he has eaten many years' worth of pizza ahead of Luis

Why would you ask "How is this possible" when you expect the answer to be "it's not"?

i can't fathom this being real, most probably this was made for karma farming or something.

Commendable for the kid to be thinking outside of the box, and a bit shitty of the teacher for not giving them maybe half a point (because it's a correct answer, but not the correct/expected answer). The test maker is also to blame - they should've taken care to eliminate all ambiguity - it's a math test after all.

The statement and question make perfect sense. The kid has the only "reasonable" answer.

I... Um... I've been looking at this for a minute and I can't tell why the answer is unconventional, nor what the fuck the teacher is on about.

If you state that Marty ate more as part of the question, you cannot answer in any other way, because it denies mathematical logic here. You introduced a lie as part of the problem, and if I need to decide myself which part of the statement is a lie, I can pick whatever I want, let's say, Marty didn't ate 4/6, but 6/6. This teacher should be taken to the gulag.

Take that to the principal, stupid teachers shouldn't teach

The equivalent of whats going on in the teacher’s head.

Given 4/6 x > 5/6 y therefore x > 5/4 y

Marty's Pizza must have been more than a quarter larger than Luis'. The kid is exactly right.

And the teacher is not flexible enough to engage outside their expectations for how the question was supposed to be answered.

Clearly the expectation was for the kids to take the unstated assumption that the two pizzas were of the same size, and reject the premise as unreasonable (note the heading "Reasonableness").

It is entirely possible and his answer was correct. Question was phrased incorrectly, if the teacher wanted an answer "it is not possible" he should have said both pizzas were the same size.

I can't find it now and I do not think it really applies here. But someone stated that being high IQ could lead to academic problems as the high IQ learner would understand or see things that the professor could not causing the professor to mark it as incorrect.

I guess this is the idiocracy version of it.