Why Can't You Score a Perfect 60 on Quant or Verbal? My Theory.

Do you have any student that has actually answered all counted questions correctly on a real test?

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Not that I know of (not all of my students have had the benefit of / taken advantage of the Enhanced Score Report, which provides some of this information). It would be helpful to see an ESR from someone who got every question right, but I haven't seen one of those yet (maybe because it's virtually impossible!).

That being said, there have been been thousands of debriefs on GMAT club, and not one of the section scores I've seen has been higher than 51 on either Verbal or Quant, other than the occasional fake one where someone got a little crazy with the Photoshop.

If someone out there has evidence to the contrary, then please feel free to disprove me. It's just a working theory of mine at the moment.

Thanks for the contribution, jennpt !

Yes, ESR research so far has confirmed that you need to answer all 30 counted questions correctly on Verbal to earn a perfect V51. In fact, just 1 wrong will drop you down to a V48.

As for Quant, you can get 0, 1, or even 2 wrong in some cases and still earn a Q51. On the other hand, I have also seen an example of a Q50 with only 1 counted question wrong.

Finally, it is also possible to score Q51, V51, 790, thus missing a perfect composite score of 800 by the narrowest of margins. This occurs when you receive a perfect score on Quant and Verbal, but answer at least one question incorrectly on Quant.

In other words, you have to answer all 58 (counted) Quant and Verbal questions correctly to earn a perfect 800.

-Brian

Hi,

It's really interesting that why GMAC doesn't disclose its grading method clearly. Why it should be a secret?:) I have another question though, what do you mean by counted question?Are there uncounted questions too?

Hi Mehemmed,

Yes, there are uncounted questions--quite a lot of them, in fact (23 of 90 total).

GMAC calls them "pretest" questions, but I like to refer to them as experimental questions. They (supposedly) do not count at all toward your score and are used for research purposes only.

On the real GMAT, there are 11 experimentals on Verbal, 9 on Quant, and 3 IR, for 25.6% of the test.

-Brian

Thanks for the info. I knew that there are experimental questions on GRE, but I wasn't aware of that is the case on GMAT as well.

One of my students answered every Quant question correctly and received a Quant score of 51.
Here's the Quant portion of his ESR:

The 0-60 scoring scale is just a legacy from the old days of the GMAT. I've seen GMAT Quant scores from around 1980 (if I remember correctly) that were outside of the current 6-51 range. As I understand (it's actually hard to find information about what the test was like forty years ago) the test used to be longer, which meant that the test was able to distinguish between test takers at a greater number of levels. A short test can't tell the difference between a V51 and a V60, so there's no reason to extend the scale beyond V51. That should make sense; we know that even one wrong answer means a test taker is below a V51 level. So when a test taker answers everything correctly, the test only knows that the test taker is at least a V51. The test would have no information at all to then decide whether to give a test taker a V51, a V53, a V57 or a V60. And it wouldn't make sense to give the test taker with one wrong answer a V49, and the test taker with no wrong answers a V60, because then the test would make a minuscule difference in performance appear to be a massive difference in ability. That's even more the case when the current V51 test taker is often one who got down to 50-50 on a question or two, and made the right guesses, while the V47 or V49 test taker did the same and made the wrong guesses. To give those two test takers Verbal scores that differ by 11+ points would not correctly report the difference in their ability.

In Quant, the situation is a bit different, because Quant questions can be harder than Verbal questions, and even a short adaptive test full of hard questions can distinguish moderately well among test takers at the higher end of the scoring scale. So in theory, the Quant scoring scale probably could extend beyond the current Q51 maximum (that's clear anyway because you can get a Q51 with a wrong answer or two), but I don't see how they could meaningfully extend the scale all the way to Q60 without making the test longer, which is something they don't want to do. It's also unclear what advantage there would be, when you consider what the test is for.