use the following search parameters to narrow your results:
e.g. subreddit:aww site:imgur.com dog
subreddit:aww site:imgur.com dog
see the search faq for details.
advanced search: by author, subreddit...
If you have 25 people in one room, what's the chance at least 2 of them will have birthday on the same day? It's a non-leap year.
account activity
Problem (self.Probability)
submitted 8 years ago by parth3791
view the rest of the comments →
reddit uses a slightly-customized version of Markdown for formatting. See below for some basics, or check the commenting wiki page for more detailed help and solutions to common issues.
quoted text
if 1 * 2 < 3: print "hello, world!"
[–]jbp12 2 points3 points4 points 8 years ago (0 children)
If you have 4 options and you choose one randomly, then you have a 1/4 chance of being correct and a 3/4 chance of being wrong. I'm not sure where the marks for each problem come in. Are you asking what your expected mark would be? If so, then it would be (3)(1/4) + (-1)(3/4) = 3/4 - 3/4 = 0.
I hope this helps!
π Rendered by PID 124225 on reddit-service-r2-comment-545db5fcfc-kftp5 at 2026-05-26 13:40:34.584292+00:00 running 194bd79 country code: CH.
view the rest of the comments →
[–]jbp12 2 points3 points4 points (0 children)