The T-Score Formula. The t-score is a fraction. The numerator is the sample's mean minus mean of the group you are comparing the sample to, and the denominator is the sample's standard deviation divided by the square root of the sample size.
If you have smoked marijuana then the drug will stay for 3 to 30 days. This is normal for the common drugs. But in the case of marijuana, this can be detected even after a month in Urine drug test marijuana. Marijuana will stay in your system for 10 days if you have been smoking occasionally.
Marijuana Stays in your system for 31 days.cocaine however will only be about a week.barbiturates will only stay 1 day, where as opiates stay about a week, except they take 1-â¦ 3 days to appear on a test.stimulants stay in your system four days, and methamphetamines will last about a week.