Originally Posted by uhduh camping
Just to confuse you more, you will have 70 Amps less.
Correct, as stated a 50 amp 120/240 volt split phase service consists of two poles/legs, each at 50 amps or 100 amps (12000 watts) total.
A 30 amp 120 volt single phase service consists of one pole/leg, at 30 amps (3600 watts) total.
This link may help explain it better, and also the use of the adapter you have that will share the 30 amps across both legs to your RV
Electrical Tutorial - Chapter 3 - 30 Amp versus 50 Amp