You're right in that calculators have replaced manual calculations at higher levels, but even my own kids, who are all strong in math, learned to work without calculators until late middle school. You're also right in that the physics/math relationship is stronger than the chemistry/math relationship.
However, math courses are required for either major, and most chemistry majors will require at
least calculus, probability, and statistics. And while calculators are used in high school and college, nearly all college-bound students have learned to do the basic multiplying/dividing manually. All that was asked in the cattle market challenge was to
find an average. Granted there was a lot of noise and activity going on, while also being under intense pressure, but it shouldn't have been too hard for someone with a bonafide chemistry degree.
But Rachel yelled out, "I'm not good in math!" So, one has to question how she got a degree in Chemistry. Maybe she barely passed. Maybe it was from a college/university that didn't require much from the student. If she really has a chemistry degree and can't find an average without a calculator, I'd be embarrassed representing that college/university. Just my opinion.