Ok so villain is 22/5
SB ($2.35)
BB ($5.39)
UTG ($3.05)
UTG+1 ($5.60)
MP1 ($1.75)
MP2 ($5.21)
Hero (MP3) ($4.93)
CO ($5.04)
Button ($3.02)

Preflop: Hero is MP3 with 10, 10
4 folds, Hero bets $0.17, CO calls $0.17, 1 fold, SB calls $0.15, BB calls $0.12

Flop: ($0.68) 7, 2, 9 (4 players)
SB checks, BB checks, Hero bets $0.68, CO calls $0.68, 2 folds

Turn: ($2.04) 5 (2 players)
Hero bets $1.02, CO raises to $4.19 (All-In)

ok so i have JJ-99,77,55,22,A9s,86s,A9o in his range against which i have 33.33 % equity against. And i only need 30% for it to be a call. However my problem is, should i really keep a9 in his range? if you make it only 9 combos of a9 (as opposed to 12), my equity shrinks to 29%, making this ev- and obviously as i drop a9 combos my equity plummets.

Buy in full.
Flop size is fine.
Turn size is also fine.
Bet/fold the turn though.

Google "Baluga theorem".