10/20 - Easy fold with middle pair?

[Bill Ivey]

Full Tilt Poker Game #3814462982: Table Butternut (6 max) - $10/$20 - No Limit Hold'em - 16:27:50 ET - 2007/10/10
Seat 1: dsindy ($2,195)
Seat 2: draizen ($1,920)
Seat 3: HisXLNC ($2,080)
Seat 5: Legend ($286)
Seat 6: chunjung ($2,866.15)
Legend posts the small blind of $10
chunjung posts the big blind of $20
The button is in seat #3
*** HOLE CARDS ***
Dealt to HisXLNC [Kh Jc]
dsindy folds
draizen raises to $70
HisXLNC raises to $240
Legend folds
chunjung folds
draizen calls $170
*** FLOP *** [2c Kd Ad]
draizen checks
HisXLNC bets $300
draizen raises to $900

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He is playing 30/18 over 25 hands, we were playing 4 handed at a different table and I have 3bet him a few times and he seems to flat call more than usual.

I check behind on the flop sometimes, but I decided to bet because I thought he had a mid pair. What are the chances he C/R's AQ here?