100k in debt

I just consolidated my credit cards into a 35k loan at 20 percent. As for the rest.. 30k in previous DCL between 10 and 29 percent, upgrade cards 4k at 29% 12k at 22%. Which gets attacked first? Highest interest or highest balance? I get a quarterly bonus of 7500 which can go directly to bills and have 3k in cash per month liquid after bills are paid. I want to be debt free in 18 months is it doable?