That looks pretty crazy to me Kristina!! But I am hopeless at maths...
It seems to be tieing the idea of bolusing for you carbs with a correction dose... why not just do them seperately?
It looks like you have an I:C ratio of 1:10 (1 unit:10g carbs)... and an Insulin sensitivity factor of 1:25, were those stated? Assuming that's the case... (sorry if they are not)
Here's an example of an alternative way to do it:
You are 200 and you are about to eat 50g carbs.
You would like to end up at 100 at the end of it all.
First the meal:
50/10 = 5 units to be taken
Then the correction:
100/25 = 4 units to be taken (100 being the difference between current and desired BG)
Total = 9 units
A bit simpler maybe? It also means you can more easily just take for the meal, or just take a correction. Specifically knowing your I:C ratio and ISF means you can adjust up and down if needs be, if you are comfortable doing so (some may feel confident to do so without talking to their doc, otherwise in conjunction with your doc), Good work in working with these calculations, whichever way you use!