4 points
While the US system gets called 110/220, my house actually puts out ~242v. Right now I have a smart plug saying 121.5v.
And since you mentioned the word “plugs”, here are our 220 15a and 20a outlets.
3 points
120/240 is the nominal voltage in North America. 110/220 is archaic/colloquial/wrong.
2 points