this post was submitted on 21 Dec 2023
39 points (86.8% liked)

Ask Lemmy

26753 readers
1395 users here now

A Fediverse community for open-ended, thought provoking questions

Please don't post about US Politics. If you need to do this, try !politicaldiscussion@lemmy.world

Rules: (interactive)

1) Be nice and; have funDoxxing, trolling, sealioning, racism, and toxicity are not welcomed in AskLemmy. Remember what your mother said: if you can't say something nice, don't say anything at all. In addition, the site-wide Lemmy.world terms of service also apply here. Please familiarize yourself with them

2) All posts must end with a '?'This is sort of like Jeopardy. Please phrase all post titles in the form of a proper question ending with ?

3) No spamPlease do not flood the community with nonsense. Actual suspected spammers will be banned on site. No astroturfing.

4) NSFW is okay, within reasonJust remember to tag posts with either a content warning or a [NSFW] tag. Overtly sexual posts are not allowed, please direct them to either !asklemmyafterdark@lemmy.world or !asklemmynsfw@lemmynsfw.com. NSFW comments should be restricted to posts tagged [NSFW].

5) This is not a support community.
It is not a place for 'how do I?', type questions. If you have any questions regarding the site itself or would like to report a community, please direct them to Lemmy.world Support or email info@lemmy.world. For other questions check our partnered communities list, or use the search function.

Reminder: The terms of service apply here too.

Partnered Communities:

Tech Support

No Stupid Questions

You Should Know

Reddit

Jokes

Ask Ouija

Logo design credit goes to: tubbadu

founded 1 year ago
MODERATORS
Bluetreefrog@lemmy.world
candyman337@lemmy.world
TheSaneWriter@lemm.ee
TheSaneWriter@lemmy.thesanewriter.com
candyman337@sh.itjust.works
Asudox@lemmy.world
can@lemmy.ca
lemmy_bot@lemmy.world
beefbaby182@lemmy.world
AsudoxDev@programming.dev
39
What are the odds of getting a passing grade by sheer guessing here? (lemmy.world)
submitted 10 months ago* (last edited 10 months ago) by FatTony@lemmy.world to c/asklemmy@lemmy.world
27 comments fedilink hide all child comments
 

Hi,

I just did a test which had two multiple choice questions. Each question was worth one point. Getting them both right would result in getting a 100% score. Suffice it to say, getting just one question right would give you 50% and with that a passing grade.

So you have two multiple choice questions. Both of which are unrelated to the other. Each question has four possible answers. When you finish the test. You get to have one more try. The questions and possible answers remain the same.

Let's say you use both tries and you remember your previous two respected answers. What would your odds be, if you were to brute force guess your way through this test, to get a passing grade or a 100%?

Edit: Both questions only have one correct answer.

IMPORTANT EDIT: YOU DO NOT KNOW WHICH ANSWER YOU HAD RIGHT OR WRONG THE SECOND TIME AROUND. You only know how many questions you got right. But you don't know which. Sorry for the confusion!

you are viewing a single comment's thread
view the rest of the comments
[–] Nibodhika@lemmy.world 3 points 10 months ago* (last edited 10 months ago)

There are a couple of errors, that I could spot, but I just woke up so my math might also be wrong hahaha.

(0.25)(0.25)=0.0625, you have a 6.25% of getting a 100.

Correct

The other option to get a 50 is (0.25)(0.75)=0.1875, 18.75%.

Almost, that's only true if the first one is the one you get right, but you can also get the second one right (3/4 * 1/4), meaning that it's double your answer, or 37.5% chance of getting at least one right.

So there is a 75% chance of failing both.~

56.25% as per above

~If you get a second chance and can remember your two wrong answers, each problem now has only three options. To get each right, (0.33)(0.33)=0.1089, 10.89% chance.

That assumes you got both wrong the first time around.

To get one right, (0.33)(0.67)=0.2211, 22.11% chance. 67% chance of failing both a second time.~

Same as above, also same as getting the second one right.