Ok, so this is the equation I gave

%fold * $wonF + [ %called * %W * $wonC + %L * $lostC ]
(.809 * 150) + [ ( (.191) * (.31 * 1050) + (.69 * -950) ) ]
terms: $wonF = Money Won when they Fold
%called = Percentage called
%W = Percentage your hand wins vs their range (or the equity your hand has vs their range)
%L = 1-%W (or the equity their range has vs your hand)
$wonC = Money won when called and you win
$lostC = Money lost when called and you lose

Say, like you said, blinds are 50/100, 1000 stacks

we know he folds 85% of the time to our open-shove, and calls 15% of the time
when he calls, we win 37% and lose 63%  

(all of the above numbers were randomly made up)

so we start out with this

[ (.85 * 150) ]

(85% of the time, we win 150 chips...

this is because there were already 150 chips in the pot when the hand started (blinds, 50 + 100), and we shove, he folded, we collected them

now we move to the next part

[ (.85 * 150) ]  +  [ (.15)

[ (.15)     is the 15% of the time that he calls us, this is the beginning of the second half of the equation

so when he DOES call us, we win 37% and lose 63%, so lets start that section

(.37  *   X)  -  (.63  *  Y)

37% of the time we win X amount, and 63% of the time we lose Y amount

now for X and Y, we need to figure these out

we have 1000 chips, and put 50 in the middle and he put 100, so there are 150 chips in the middle, and he has 900 more we can win. Therefore if we win, we win 900 (his remaining chips) + 150 (whats already in the pot), so this is where the number 1050 comes from.

Now lets look at if we lose. We already have 50 in the middle (mandatory... its a blind), so we can only lose 950 more

(make sense??)

so our final equation would come out to

[ (.85 * 150) ]     +    (.15) *  [  (.37 * 1050) - (.63 * 950)  ]

Hope that helped, let me know if you need any more explanation!!!