Grammage is specified in avoirdupois pounds and the sheet count of a paper ream is usually 500 sheets. However, the mass specified is not the mass of the ream that is sold to the customer. Instead, it is the mass of the uncut "basis ream" in which the sheets have some larger size (parent size). Often, this is a size used during the manufacturing process before the paper was cut to the dimensions in which it is sold. So, to compute the mass per area, one must know The standard dimensions and sheet count of a ream vary according to the
Ruled paper lighter lines 2 mm (appx. 5/64 in) apart between each pair of heavy lines. Heavy vertical lines are spaced 8 mm (appx. 5/16 in) apart, beginning 16 mm (appx. 5/8 in) from the left-hand edge of the page. These sheets of paper are generally known as "grands carreaux" (large tiles) as opposed to the "petits carreaux" (small tiles) which are 5x5mm. Seyès ruled paper is available in single sheets ("copies simples") or joined double sheets ("copies doubles") which are sometimes preferred for exams, being easier to handle. DIN 16552:1977-04 (“Lines for handwriting”) specifies the types of ruled paper to be