writing to review/helps with understanding

#1
I'm currently trying to grasp the concept of z scores before heading into confidence intervals (which is the next stage of the hw) z scores use the mean and sd to establish how far a 'score' is from the mean(in sd units). You then take the score and convert it into a probability. Question: How do you know which probabiliy to use? My table has a z score with negative and positive. A simple solution I'm sure, but I'm having difficulty making sense of it. (1st stats class)
Rick
 

JohnM

TS Contributor
#2
In our Examples section there is a post entitled "The Vaunted Distribution." This may help - it talks about the 4 possible scenarios or probabilities that could be asked for.