# events

1. ### Total complications in both groups

Hi, I have the following question: In my study I compare two kinds of surgery options. Group A has 9 patients and group B has 6 patients. When comparing the seperate complications there is no significant difference. But now I want to compare the total of complications between group A and...
2. ### Independent events occurring simultaneously

Hey guys, I saw a similar question on the site, but still need some help with my own. Here it is: Consider a double computer intruder detection system with system A and system B. If there is an intruder, system A sounds an alarm with probability .95 and system B sounds an alarm with...
3. ### Probability on 2 random events combined

event A and B are not related but : if A happens then the event C has a probability W of happening. if B happens then the event C has a probability Z of happening. if both conditions happen A and B, Is the probability of C happening the combination of probabilities, W*Z then? Thanks