Maybe. Hard to tell from that description.
On your TI-84, please read up in the invNorm() Function. It will guide you in the way that you should go. [2nd][VARS] to get to the DISTR menu.
You need invNorm(0.1515,0,1). I get -1.03002 wich seems to be consistent with what you were trying to tell me from your book.
Learn how to use that calculator, too! It can be a valuable tool, but not if it is just a black box. Seriously, force yourself to read it and physically press buttons to replicate ALL the examples. It will help you if you make it your friend.