Fold fourth.

But to answer seriously, if you started with 6A54 then bricked twice, you are looking to catch a 2, 3, 7 or 8. You have 12 outs, but seat 1 has one of your outs. Of 52 cards in the deck, 14 are known, so your 11 outs are in the remaining 38. So it's 27:11 = 2.5:1. Since you are only playing for half the pot you need to be getting about 5:1 I think.

Someone feel free to correct me, because I did it in my head, and I might be wrong anyway.

Simple answer: You're probably getting the right odds, so call.