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11:18 AM
It seems it took 9 votes to delete this question. I suppose that's because it had 30 upvotes? Anyway, currently it has 7 undelete votes. Does it need 9 to undelete? — Gerry Myerson yesterday
I suppose that the number of votes necessary to undelete is the same as number of votes to delete.
I searched a bit on Meta Stack Exchange, but I did not find something where this is clearly document. Although there are some posts related to this topic, for example, How many votes are needed to undelete?
Oh, now I notice this:
51
A: Should delete votes be limited like close votes?

Jarrod DixonWe had discussed this before, but deferred until there was a problem - it seems we now have a problem :) The new rules (also apply to undelete votes): 10k rep users get 5 deletion votes per day on questions they don't own, increasing by 1 vote per extra 1,000 reputation up to 30 votes per day ...

That post explicitly says (emphasis mine):
> The new rules (also apply to undelete votes)
 

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