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Square Units

Title text: The biggest I've seen in a published source in the wild is an 80-fold error in a reported distance, which I think came from a series of at least three unit conversions and area/length misinterpretations.

Explanation

In this comic, Megan has found an insect species on her phone that devours one square inch of grass per day. This unit gets misinterpreted 11 times until Hairbun tells other people that it devours an area of grass equal to two times the land area of Australia per day, which is clearly impossible by one insect.^{[citation needed]} This is similar to the premise of 2585: Rounding.

This gross error is the result of repeatedly misinterpreting the number of square units as the side length of a square, thus increasing the described area by the power of two. The chain also involves converting between an imperial unit and a metric unit, alternating, thus introducing smaller rounding errors even while switching which measurement is "a single square with sides of a certain distance" and which is "the number of squares that are each of unit length". The upshot is that, while each statement has two roughly similar measurements of area, the chain of misunderstanding ends up claiming ever larger relative expanses. The later participants in this chain also clearly forget to sanity-check their figures, blithely informing others that an individual insect is effectively consuming impossibly huge quantities of food, and travelling enormous linear distances every day to do so.

The title text tells us that Randall once found an 80-fold error in a reported distance in a published source.

Transcript

[Arrows point to each consecutive panel.]

[Megan is looking at her phone, with Cueball standing next to her.]

Megan: This newly-described insect can devour up to a square inch of grass per day.

Cueball: Oh, neat.

[Cueball is speaking to Ponytail.]

Cueball: ...it eats a square inch, or 6 cm², of grass per day...

[Ponytail is speaking to Hairy.]

Ponytail: ...a 6-centimeter (2½ inch) square of grass, or 36 cm²...

[Arrows now point to each consecutive conversion.]

Written out of panel: ...a 36 centimeter square, or over a square foot...

Written out of panel: ...a square foot, or 900 cm²...

Written out of panel: ...a 900 cm (30 foot) square...

Written out of panel: ...a 30 foot square of grass (900 square feet)...

Written out of panel: ...a 900 foot square, or almost 20 acres...

Written out of panel: ...20 acres (8 hectares, or 80,000 square meters)...

Written out of panel: ...an 80,000 meter (80 km) square...

Written out of panel: ...a square 80 km wide, or roughly 2,500 square miles...

Written out of panel: ...a 2,500-mile square, or twice the land area of Australia, per day...

[An arrow points from the last conversion to the last panel.]

[Hairbun is looking at her phone, with White Hat, Danish and Blondie standing next to her.]

Hairbun: Did you hear about this insect that defoliates the entire land area of Australia twice a day?

White Hat: Gosh!

Danish: Wow.

Blondie: I hope at least it's contained there...

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