United ordered 76 737-222s, but took only 75...the 76th was built & delivered elsewhere as originally ordered.
I can't speak for the 76th, but the Air Florida crash at DCA
in 1982 was an ex-United 737-222, N9050U:
As far as Boeing goes, the 727-100 model is the only Boeing commercial plane that came with the possibility of a two-digit system after the 727, such as a 727-22. Boeing's 707's all had a -100, -200, -300, or -400 designation, and as stated, once the 727 was offered as a larger model, the -100 and -200 system was designed.
Even planes that have one basic form use a model designation - the 757 for many years was only available in one model form, yet it was always called a -200. When the -300 came along, there was no confusion over designation.
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