RPGs are unguided. The odds of an RPG accurately hitting a commercial aircraft at speed (in flight) is very, very low even at relatively close range. They are more of a threat for helicopters.
Shoulder-fired guided missile systems (MANPADS) like Stingers and SA-7s can be deadly at short ranges. According to the US State Department, since the 1970s MANPADS have hit at least 40 civilian aircraft, causing over 800 deaths.