Normal 2:3 pulldown would alternate doubling or tripling frames. 12 x 2 = 24, 12 x 3= 36. 24 + 36 = 60 the refresh rate for most sets in North America or NTSC lands where mains alternating current is 60hz. This would be true for progressive or interlaced displays at 60hz. For 120 hz display it is possible , depending on playback system and display , to correctly show 24p, ie display each frame 5 times just like a 5 bladed film projector. I have a 3 bladed and 5 bladed film projector ( originally intended for telecine ).
Ron Evans
