chances of flopping a straight with J9

just trying to sharpen my math skills here. i picked a random hand and wondered about the chances of flopping a straight with this hand. im sure i went wrong somewhere, but is 0.66% anywhere near close?

J9 can flop 3 straights, right? (using BOTH cards) 7-J, 8-Q, 9-K. the chances of flopping a straight using any of those boards is 0.32%, correct? this is purely for curiosity and would appreciate any replies *COUGH BruceZ COUGH*