Lemme see here.............If I try to see when dividing is appropriate and when multiplying is appropriate, I guess I'd start by imagining an appliance which consumes....let's say......10 Watts of power. If it were to run for one hour, then I would say that it used 10 W * 1 hour = 10 Watt hours of electricity. If it ran for 2 hours, then I would say that it used 10 W * 2 hours = 20 Watt hours of electricity. Is that correct? And is the proper abbreviation 20 Wh?
Looking at it from the other end......If I knew that an appliance had consumed 20 Wh of electricity and I also knew that it was rated at 10 W, then I could calculate that this appliance had run for 20 Wh/10 W = 2 hours.
And if I keep going down this road, I'll only confuse myself. At first, anyway.
Plus.....you've already been helpful by simply planting this question in my mind. There's no need for me to impose on your time and effort with further explanations. (Though if you see some awful error above which simply can not be allowed to stand, then I'd appreciate a 'heads up'.)
I'll simply keep in mind that I'd better nail down these abbreviations. I'll try to learn it by reading these threads. And I'll start by keeping in mind that a 'forward slash' definitely implies division.
Thanks and I'll see you around!