Hey guys,

I've run into some trouble with implied odds situation on the flop when we bet and face a c/raise. For example a hand like this http://www.handconverter.com/hands/2843285
Spots where we face just a bet I've been using the simple solution from a book "Poker math that matters".
It looks like this:
https://gyazo.com/a8261f3884d27838cd88d16d5227893e
Ex I have 15% to improve to turn (assuming I face a bet 100% OTT and never get a free card). He bets 10 into 10 so we divide it by 6
10x6`= 60 and now we subtract the pot size from this 60-20=40 or more is what we have to win OTT to make the call.
But what number to use when doing the same thing with the exception of already having invested into the pot.
Now coming back to the AAQT hand example, should I use his raise size , or the size that i have to call?
I think the call size makes more sense but I just wanna be sure since it makes a big difference.

Thanks in advance