From the January 2016 Common Core Algebra I Regents

Key questions to ask about this literal (only letters no numbers) equation;
But first a regular looking equation of 5x = 10
How do you solve 5x = 10?  (s’s will say divide by 5)
So how many x’s?  (5)
see below for an example of a literal equation

We divide both sides by r because that is how many t’s there are!! r t’s

How many r’s are in Prt?
There would be Pt r’s in Prt so we would start with
I = Prt and divide both sides by Pt
so that would be I/ Pt.

2 points 🙂