voltage divider - ohm value
The load is defined to be 27.5ohms. That's in figure 3-64 of your link. It doesn't say it anywhere, but it does give you the voltage and the current.

This is the problem with voltage dividers supplying any significant load, they have no voltage regulation. If the load changes, then the delivered voltage changes.

The extra 275ohm resistor in shunt with the load is one of those things I call 'unnecessary and insufficient'. It's not sufficient to regulate the voltage, and it's not necessary to get the right voltage given that you have to muck about calculating correct resistor values anyway. Your 82ohm would have been just fine.

What the article should really say is that 'you would never drive a load this low with a voltage divider, but if you did, and if you wanted to divert 10% of the load current round the load just for the heck of it, then these are the resistor values you'd use.' 

Now if you diverted (say) >100x the load current round it, then you'd have reasonable regulation, but you'd need your load to be very low current to be even remotely efficient. You did the sums for a 10M load.

Not every tutorial on the net is actually noob friendly, not necessarily even if it claims to be.