Nature has found a way to evolve a spider into the size of a smallish elephant. Let’s say, 15 feet from the ground to the top of its bristly back.
For the math, let’s give it a physiology similar to that of a tiger, so this dude is warm-blooded, and if we need to we can give it an internal skeleton to compliment it’s chitinous exoskeleton. It’ll need lungs, I expect. It spins webs.
So. How many 150 pound humans would this bad boy need to eat in a day/week in order to survive?
You’ve made so many changes to the spider to make it that big, I’m not sure any comparisons to modern spiders would make sense any more.
It’s still a cold-blooded ambush predator, though, so it probably would be analogous to a croc or a snake. It would probably be able to go weeks or months between meals the size of a human, but would happily eat ten times that much if the food was available.
One ring bearer, with a side of gardener. I read it in a book somewhere.
The interesting question, seeing as WE are the top predator, is “what’s it taste like”?