I have dyscalculia. It's not the inability to do math, really, it's a disconnect between math logic and the visual cortex. If I see a more than four numbers on the page at a time, I'm screwed. This is why all the spreadsheet attempts people have made, while well meaning, are completely useless.

I've been able to do this boss by saying the question out loud instead, bypassing the visual cortex which is still counting in potatoes and leveraging the audio parts of my brain instead.

I AM TWO
HE IS ASKING FOR A PRIME NUMBER
FIVE IS A PRIME
FIVE MINUS TWO IS THREE

^ Doing this visually is not instant for me. Doing this via an auditory hack is amazingly much faster because as soon as I say "five is a prime" the math circuits activate properly.

Looking back, I survived all my math classes by learning to recite whatever I was doing with my internal narrative monologue. Long division is still my personal hell. I did fine once I reached algebra.