Where's the 2.84 x 100 coming from?

Let me try this:

You have $2.17 to call into a pot of $3.34, and you have 55% equity. So 55% of the time you win $3.34 and 45% of the time you lose $2.17.
That is an expected value of (0.55 x $3.34) + (0.45 x -$2.17) = $0.86, so I call every time.

Right?

As for villains raise, I guess it depends on his fold equity, which is down to his opinion of your range, so hard to tell.