Unfiltered Story #259809

Many years ago I was a teaching assistant to a general (i.e., inorganic) chemistry course. We held “recitation sessions” which principally were to aid students in understanding course materials.
Now, algebra is a prerequisite to general chemistry, so all students were expected to understand algebra. (If the reader does not, that’s okay. There’s no algebra prerequisite to life!)
So one day I was explaining something involving a calculation, probably the ideal gas law, and had an equation on the board like:
P*V=n*R*T
and I rearranged it to something like
n = P*V / (R*T).
Immediately a hand went up and the student asked me how I got from the one to the other. Well, admittedly, I didn’t show all the steps, but most folks conversant in algebra don’t need to be shown all the steps. So I elaborated, along the lines:
P*V=n*R*T, whence
n*R*T=P*V, whence
N*R*T / (R*T) = P*V / (R*T), … and before I got any further, the same student’s hand went up for a further clarification.
This went on over an over through what should have been an obvious algebraic manipulation, till it was clear all the other student were getting impatient with the questioner. At which point I told him to review algebra, and went on the the meat of the discussion.