Use this link to determine your tournament equity.
http://sharnett.bol.ucla.edu/ICM/ICM.html
Find your equity if you win.
Find your equity if you lose.
Find your equity if you fold.
Multiply your win equity by your hand's equity against his range. Do the same for you equity when you lose and the percentage of times he loses. Add these two numbers together compare to equity if you fold.
Sorry if I wasn't very clear.
Here it would be for your hand
(.456)(equity if you win) + (.543)(equity if you lose)