The script for the 1st episode of Roman's Empire was 39 pages. That's for 28 minutes. So, I would say on average 38 to 40, maybe 41. Really, it doesn't matter as long as if funny, or whatever.
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Probably it depende on how many words there are.
I think if you write 40 - 50 then at least you've got too much, rather than too little.