Question 1158229
<pre>
Since it's a one-tailed test the whole level of significance is contained in
the one tail. [If it were two-tails, it would be split half and half between
the two tails.]

On your TI-84
press 2ND, VARS,
highlight invT    <-- invT, not invZ because 25 is less than 30 

area:0.05
df:24         <-- 1 less than n
Paste

invT(0.05,24)     <-- what you should have on your screen

press ENTER

-1.710882023, which rounds to -1.711

The reason it's negative is because the calculator gives critical values for the
left tail.  Since your choices are all positive, they want a right tail, so by
symmetry, make it +1.711.

Edwin</pre>