DAY 84

Comment

The shape can be thought of as a square, with a 1 cm wide strip removed.
The strip is x cm long, so as s x gets smaller the area gets larger.
However, the square itself only has an area of 16 square centimetres.
A way to resolve this is to let x take negative values, and to interpret this as 'sticking out' of the square rather than 'sticking in'.

Answer

Readers' methods

Vicky, Jaipur:
Rather than cutting a bit out of the 4 cm square, I stuck a bit on (a 1 cm square).

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