Never say to an autistic person "you do the math"
This is actually an inaccurate perception.
Autistic children are very adept at math. The more concrete the facts, the better. 2+2 will always equal 4. It's a fact that can be memorized and retained.
It's the abstract thinking that trips them up. Language Arts (reading comprehension and interpretation, writing, etc) are the major stumbling blocks in autism. Figurative thinking does not come naturally. Ask an autistic child what time it is, he'll be able to tell you. Ask him to describe a time when he was happy, he'll have a problem.
Now, 40 lashes with a wet noodle for you, Wacky, for making me step into teacher mode during my summer vacation.