HELP! STATISTICS!!! PLEASE!! :(:(

[slisjunknown]

I urgently need any notes for normal distribution....stuff like when P(Z>a) is negative(greater than 0.5 or less)....please
THANKING U IN ADVANCE

 

[ibnatk]

When it is z>(x-mean)/sigma is negative, you just flip the mean and X. make it z>(mean-x)/sigma