- British Area
- 1 sq foot = 144 sq inches
- 1 sq yard = 9 sq feet
- 1 sq rod = 30.25 sq yards
- 1 sq chain = 16 sq rods
- 1 rood = 2.5 sq chains
- 1 acre = 4 roods
- 1 acre = 160 sq rods
- 1 acre = 4840 sq yards
- 1 sq mile = 640 acres
- 1 sq mile = 1 section
- 1 township = 36 sections
- U.S. Area
- 1 sq foot = 144 sq inches
- 1 sq yard = 9 sq feet
- 1 sq rod = 30.25 sq yards
- 1 acre = 160 sq rods
- 1 sq mile = 640 acres
- 1 sq mile = 1 section
- 1 township = 36 sections
- 1 township = 6 miles square
- Geometric Figures
- Square – square of a side (A = s2)
- Rectangle – length times width (A = l x w)
- Circle – pi times radius squared (A = 3.1416 x r2)
- Triangle – one-half times base times height (A = 1/2 x b x h)
- Trapezoid – one half times sum of the two parallel sides times height (A = 1/2 x [parallel side 1 + parallel side 2] x h)
- Parellogram – base times height (A = b x h)
- Lateral Surface of a Cylinder – two times pi times radius times height (A = 2 x 3.1416 x r x h)
- End Surface of a Cylinder – two times pi times radius squared (A = 2 x 3.1416 x r 2)
- Total Surface of a Cylinder –
- lateral area plus end areas (A = [2 x 3.1416 x r x h] + [2 x 3.1416 x r 2]
- Lateral Surface of a Cone – pi times radius times slant height (A = 3.1416 x sh)
- End Surface of a Cone – pi times radius squared (A = 3.1416 x r2)
- Total Surface of a Cone – lateral area plus end areas (A = [3.1416 x sh] + {3.1416 x r2}
- Surface of a Sphere – four times pi times radius squared (A = 4 x 3.1416 x r2)
- Metric
- 10,000 sq. metres = 1 are
- 100 ares = 1 hectare
