DAY 04

Comment

For all the shapes, the total length of the horizontal 'steps' is the same as the base of shape F, say.
For all the shapes except C, the total length of the vertical 'steps' is the same as the height of shape F.

(It is tempting to take this further and to argue that if the steps are made small enough, so that you get a shape that looks like the triangle PQR, then PQ must equal PR + RQ, though we know this is false ... .)

Answer

C is the odd one out. (It has a slightly larger perimeter than all the rest.)

Readers' methods

H Morton, of Oxford OX2:
For all the shapes except C, you can get from the top left hand corner to the bottom right hand corner by going Right a bit, Down a bit, Right a bit, Down a bit, etc. For C you have to go Up on one occasion.

xxx