# Math Help - p values

1. ## p values

can anyone tell me how to find the p values for a z-score of 1.38 using the formula
_
x - score
variance/squareroot n

2. Originally Posted by purcey_36
can anyone tell me how to find the p values for a z-score of 1.38 using the formula
_
x - score
variance/squareroot n
Pr(Z > 1.38) = 0.0838. Get it from technology (I used a TI-89) or from tables.

3. That's correct if you have a greater than sign in the alternative hypothesis.
This cannot be answered until I know $H_a$.
It doesn't matter if we are testing a mean or a proportion, we need $H_a$.
AND if $H_a:\mu\ne 21$, then the p-value is twice this 0.0838.