zdeminador

For example on the SAT if I get four Ds in a row does that mean that it is very likely one of them is wrong?

xthrillakillax

Not necessarily, there have been instances where four in a row were all right. Assuming absolute randomness, the probablity of getting the same answer four times in a row is 1/125. I wouldn't worry about the pattern in your answers too much; just go with what you think is the best answer. For example in the June 2012 SAT on one of the Improving Sentences part I must have gotten like 20 B's. I got really paranoid and I wasted valuable time triple checking every answer. Later I learned from my score report that I got all the Improving Sentences questions right. It just goes to show that you should go with your gut and not worry about the pattern too much.

Kyrix1

No.

There is a 1/625 chance you get DDDD, 1/625 chance you get AEBD, 1/625 chance you get CCDA, etc. Since you're just talking about 4 in a row, we can multiply that by 5 to get 1/125. Thus, given enough practice problems (which isn't much, actually, if you're serious in prepping), you're more than likely to get 4 in a row.

edit: sniped

rspence

2012 AMC12A. 'Nuff said.

Kyrix1

^that

PS imo 10A was easier than 10b, just saying... (this shouldn't be here, it shoud be on aops...)

Omicron

For the SAT, I'm pretty sure the College Board does actively avoid 4 of the same answer in a row. SAT mentions it, but doesn't really offer a citation. I haven't ever seen 4 in a row for the answers on an official SAT, and I'm nearly certain it doesn't happen.

piratebay

I've never seen 4 in a row correct on an official CB SAT. If you do, however, get 4 in a row on an actual SAT, you better be completely sure all 4 are correct. I am under the belief that they actively avoid this.

cheerioswithmilk

^^^sorry, but I don't agree. It's pretty much random, and it does happen every now and then. Now if you get 9 or 10 in a row, then that might be a problem. But 4? That's pretty normal.

Omicron

Cheerios, I fully understand the probability of it happening, but I'm pretty sure that the College Board doesn't completely randomize their answers and have deliberately avoided 4 in a row. Find me an old SAT where it did happen and I'll believe you.

pckeller

First of all: there is NO pattern. And semingly "unlikely" things happen all the time if you sample long enouth. [Aside: for REALLY unlikely events, you will have to sample for so long that it dwarfs the age of the universe -- making such events effectively "impossible". That's what's going on in the thread about guessing randomly on every question and scoring a 2400. It's also how to tell a machine generated random list of say heads and tails from a human based list: the human will stay away from runs of 5 or 6 heads in a row, thinking that it isn't likely.]

In this case, I would have bet a good bit that 4 in a row does in fact happen and that the SAT does not adjust the answers to avoid this. So I picked up the blue book and started checking the answer keys, working from the back. I got to test #7, section 4 and there it is: 20 - 23 are all C. I am not going to check any others, but I bet they are there...

knowthestuff

You should judge how confident you are of an answer choice based on the current question and current answer choices. I would not judge my answer choice's validity based on previous answer choices. To me, the original poster's logic would lead to loss of focus and misguided doubts.

stressedouttt

nope. it's been known to happen

Omicron

pckeller, thanks for checking. Of course, the Blue Book's not the actual test, but I'd say it's close enough. Good to know.

DrGoogle

When my daughter took her SAT she had five in row with the same answer. But they were all correct answers.

cheerioswithmilk

If I remember, I believe that this year's PSAT had 4 in a row on the writing.

Whoops, just checked. It was three in a row; I got the last one wrong.

But yeah, as some of the posters above have said it does happen every now and then, it seems.