Wesley estimated 5.82-4.21 to be about 2. is this an overestimate or an underestimate?

I'd say neither because 5.82-4.21 equals to 1.61, and it does not go above 2 as an overestimate. In addition, it's not an underestimate because 1.61 rounds up to 2. If you can't put that as an answer, you can say its an underestimate because it does not meet the real standards of being 2.