About a gazillion. It depends on how large or small your curls are. You could try covering a cake pan the same size as your smalled tier. that would gve you a place to start.
However;
Just in case, this isn't that email inquiry from the bride who wants a price for dessert size and a tasting size? She wants a rich chocolate cake covered in chocolate curls. If it is, that email is a scam. You can find other posters here who received the same email.
JoAnn
I don't know if this will help you, but on the cheesecake in my photos, it took over 120 white chocolate curls to totally wrap the cake. It was a 9 inch cake. However, I ordered the curls Koerner's in New Orleans, and they were very thin! Keep in mind there's going to be a lot of breakage too.
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