In my playing days, I played one untimed game
that had three calculation questions. The opponents
got the full 25 on both of their answers that
required only + - X /. When we needed 25 to tie the game
on our last bonus, the editors had decided that my
calculating two dot products and a 3x3 cross product was
worth only 20 total.
Imagine my disgust.
I suspect the general lack of math questions in
recent years can be summed up by that story.
A.
They work best in untimed events. Who wants to spend
30 seconds in a timed match on one tossup by itself
(or even one bonus)?
B. They're harder to
write because you have to actually do the math to get
the answer (and should show your work after giving
the answer).
C. They're generally disliked by
humanities people who edit tournaments: you have to actually
do the math to check the answer, and if you're not a
math person, it's harder to do that than to check an
author in Benet's or on the Web.