The common letter-sized paper used in Europe and in most locations outside of North America. At 8.3 x 11.7" (210x297mm), A4 paper is slightly narrower and a little longer than "A" size 8.5 x 11 ...

A4 size paper has a long side of 297 mm and a short side of 210 mm. Regardless of 210 mm, the number of 297 mm is quite incomplete, and in fact Mr. Sparks seems to remember when his classmate said ...