In my opinion, the problem (a) should be "Prove that a square with side length 1000 can be divided into 31 square tiles, at least one of them has side length less than 1." The original problem writes "dass sich ein Quadrat mit Seitenlänge 1000 in 31 Quadrate zerlegen lässt, ...", where zerlegen: to decompose lässt: has something done, make something happen And also, the official answer is just an example decomposing the square such that the smallest square has length <1.