The following unit conversion will give you idea in detail the consepts of architectural measurement.

Inches To Millimeters			Centimeters to Inches
Inches	Millimeters		Centimeters	Inches
1/32 in	0.794 mm		0.2 cm	1/16 in
1/16 in	1.588 mm		0.3 cm	1/8 in
3/32 in	2.381 mm		0.5 cm	3/16 in
1/8 in	3.175 mm		1.0 cm	3/8 in
5/32 in	3.969 mm		1.4 cm	9/16 in
3/16 in	4.763 mm		1.5 cm	5/8 in
7/32 in	5.556 mm		2.0 cm	3/4 in
1/4 in	6.350 mm		2.5 cm	1 in
9/32 in	7.144 mm		3.0 cm	1-3/16 in
5/16 in	7.938 mm		3.5 cm	1-3/8 in
11/32 in	8.731 mm		4.0 cm	1-9/16 in
3/8 in	9.525 mm		4.5 cm	1-3/4 in
13/32 in	10.319 mm		5.0 cm	2 in
7/16 in	11.113 mm		Note: Centimeters (cm) have been rounded off to the nearest tenth of a cm.
15/32 in	11.906 mm
1/2 in	12.700 mm		Square Feet to Square Meters
17/32 in	13.494 mm		Square Feet	Square Meters
9/16 in	14.288 mm		1 sq ft	0.093 sq m
19/32 in	15.081 mm		2 sq ft	0.186 sq m
5/8 in	15.875 mm		3 sq ft	0.279 sq m
21/32 in	16.669 mm		4 sq ft	0.372 sq m
11/16 in	17.463 mm		5 sq ft	0.465 sq m
23/32 in	18.256 mm		6 sq ft	0.558 sq m
3/4 in	19.050 mm		7 sq ft	0.651 sq m
25/32 in	19.844 mm		8 sq ft	0.744 sq m
13/16 in	20.638 mm		9 sq ft	0.837 sq m
27/32 in	21.431 mm		10 sq ft	0.930 sq m
7/8 in	22.225 mm
29/32 in	23.019 mm		Square Meter to Square Feet
15/16 in	23.813 mm		Square Meters	Square Feet
31/32 in	24.606 mm		1 sq m	10.764 sq ft
1 in	25.400 mm		2 sq m	21.528 sq ft
			3 sq m	32.292 sq ft
Feet	Millimeters		4 sq m	43.056 sq ft
1 ft	304.8 mm		5 sq m	53.820 sq ft
2 ft	609.6 mm		6 sq m	64.583 sq ft
3 ft	914.4 mm		7 sq m	75.348 sq ft
			8 sq m	86.111 sq ft
Note: Some of the SI International System of Units (metric) conversions listed in these tables are rounded numbers at the third decimal place.			9 sq m	96.875 sq ft
			10 sq m	107.639 sq ft

Conversion tables
Conversion Ratios
Length and Area		Mohs Scale
Convert from To Multiply by millimeter inch 0.04 centimeter inch 0.3937 centimeter foot 0.03281 meter inch 39.37 meter foot 3.281 square meter square foot 10.763 inch millimeter 25.4 inch centimeter 2.54 inch meter 0.0254 foot meter 0.3048 yard meter 0.9144 square inch square meter 0.000645 square foot square meter 0.092990 square yard square meter 0.836127		In 1812, the Mohs Scale of mineral hardness was devised by the German mineralogist Frederich Mohs (1773-1839), who selected the ten minerals because they were common or readily available. The scale is not a linear scale, but somewhat arbitrary.         Hardness Mineral 1 Talc or mica 2 Gypsum 3 Calcite 4 Fluorite 5 Apatite 6 Orthoclase 7 Quartz 8 Topaz 9 Corundum 10 Diamond     Source: American Federation of Mineralogical Societies, Inc.
Weight
Convert from To Multiply by pound kilogram 0.4536 ounce gram 28.3495 long ton pounds 2240 short ton pounds 2000 gram ounces 0.0353 kilogram pounds 2.2046
Volume		Slab Production Table
Convert from To Multiply by cubic cm cubic inch 0.061 cubic meter cubic feet 35.3198 cubic inch cubic cm 16.387 cubic feet cubic meters 0.028 liter gallons 0.2642 lb/ft³ kg/m³ 16.02 Mpa lbf/in² (psi) 145 lbf/in² (psi) pascals (pa) 6895 lbf/in² (psi) kg/sq m 4.882 kg/m² pascals (pa) 9.807		Blocks Slabs/Foot Slab Thickness 1 cu ft 10 3/4" 1 cu ft 8 1-1/4" 1 cu ft 7 1-1/2" 1 cu ft 5 2" 1 cu ft 4 2-1/2" 1 cu ft 3½ 3" 1 cu ft 4 3-1/2" 1 cu ft 2½ 4"