How many square blocks are in 1 meter if blocks are 40 cm x 40 cm?

Answer 1

6.25 Actually, it's 6 complete blocks and a little empty space.
I'm leaving the above answer though I disagree with it a bit (no quibble with the math, but a couple of problems with the geometry).

The question is ambiguous: what is a "square block"? (It doesn't help that you say "one meter", because if you mean that literally, you cannot fit any two-dimensional (40 cm x 40cm) or three dimensional (blocks) figures in a one-dimensional unit of measurement.)

If you mean cubes, you can fit 8 solid cubes 40 cm on a side in a box 1 m on a side. You'll also have quite a bit of room left over, but you won't be able to fit any more cubes of that size in without cutting them into smaller pieces.

If you mean squares, you can fit 4 squares 40 cm on a side in a square 1 m on a side. Again, there will be room left over (this is where the extra 2.25 comes from in the original answer), but it's not possible to fit another 40x40 square in without chopping it up.