[Jtsummers]

It's not inexact, though. "and" in this case is a logical joiner not a numerical joiner. "Richard, Jerry, and Robert are going to share 60 cherries" is the first fact presented. "Robert has 30 cherries" is the second fact, it is one property about the cherries Robert has. "and has 10 more than Richard" is a third fact, it is another property of the cherries Robert has. The only addition that comes out of this is from the "10 more than Richard" bit, "more than" suggests addition, "and" does not. The way kids are taught to transform that would be something like:

  richard + jerry + robert = 60
  robert = 30
  robert = richard + 10

Trying to make Robert have 40 cherries makes the math conducted by the "AI" even more absurd, because it throws out the first fact (that there are 60 total).