I dont use all purple rollers on my hair because I am too cheap to buy more. I usually put four black rollers (maybe 1.0 in) in the front with clips and 12 purple rollers in the back. It usually takes me over an hour and thirty minutes to dry completely.
BTW, yea Datjerseydyme, those pink rollers are too small for all that hair on your hair. But keep them. I use the pink rollers when I have a lot of new growth to straighten. They're great when I am 11-12 weeks post relaxer!