Math:Fishing Whales
From Melvor Idle
Fishing one Whales takes 4.5-11.25s (which Dragon Fishing Rod and Fishing Amulet), so 7.875s on average.
That's 7.62 fishing actions per minute or 457 per hour.
Each actions grants at least four whales, so 1828 whales per hour.
+5% to receive 8 whales from 
Pudding Duckie, +10% from File:Aorpheats Signet Ring (item).png Aorpheats Signet Ring and +12% from 
Fishermans Potion IV, -3% to receive special items instead of whales = +24% = 2267 whales per hour.
Each sold at 750g = ~1.7M per hour.
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