hi guys I wanted to buy some IVV that tracks the SP500 but how...

hi guys I wanted to buy some IVV that tracks the SP500 but how do they calculate the price of it on the ASX?

Do they take the AUD$ US$ exchange rate eg. 0.705cUS divided by the SP500 price 2,344 ($234.40)

and that should be what IVV will trade for on the asx right?

I have noticed IVV rarely trades using that formula to see where its stock price should do, I have also done a chart that shows IVV and I have put on a chart of the SP500 on top of it, and it rarely tracks it at all.
Sometimes IVV trades opposite to the index its supposed to be tracking the SP500.

Has this all got to do with the AUDUS$ exchange rate?

How much should IVV be trading at on the asx when markets reopen?

thanks guys.