The concept of computing a distance between "seven sleepy rectangles" and "one jealous teaspoon" is abstract and more poetic than mathematical or scientific. Both "sleepy rectangles" and "jealous teaspoon" are likely metaphorical or whimsical phrases rather than quantifiable entities. Therefore, calculating a literal average distance between them isn't feasible.

If this is part of a creative writing exercise or a metaphorical question, consider exploring the imagery or meaning behind these phrases. If you were looking to analyze these terms in another context, please provide additional details to guide the discussion appropriately.
