
Area

square

	area = side_length x side_length



rectangle

	area = short_side_length x long_side_length



circle

	area = 0.5 x pi x (d/2)^2


triangle

(with one right angle)


	area = 0.5 x shortest_side_length x medium_length_side_length

		(not the longest side)

	

Volume

cube

	Volume = side_length x side_length x side_length 

	

rectangular block


	Volume = height x width x length_front_to_back




circumference


dinstance around an object


square

	dist = 4 x side_length


rectangle

	dist = 2 x short_side_length x long_side_length


circle

	dist = 2 x pi x (d/2)



distance = speed x time

	
	100 kmh x 3 hrs

	= 300 km




surface area

area of the square flat surfaces of a cube or block



cube

	area = 6 * side_length x side_length 

	

rectangular block


	Volume = 2 * height x width + 2 * height x length_front_to_back + 2 * width x length_front_to_back




percentages


		 percentage
	amount = ---------- x larger_amount
		     100


	8% of 200


	    8
	= ---- x 200
	   100

	= 16




conversions


	ml to litres		value x 1000


	litres to m^3		value x 1000


	mm to metres		value / 1000


	seconds to minutes	value / 60

	minutes to hours	value / 60

	hours to days		value / 24




terms


m^2		square metres

m^3		cubic metres


ml		millilitres


pi		constant/letter from mathematical alphabet, 3.14


d		diameter of a circle, the distance from one side

			across the middle to the other side




recommended units

(SI system)


time		seconds

distance	metres

area		square meters M^2

volume		cubic meters M^3

weight		kilograms

power		Watts

energy		Joules

//speed		



Size values


Thousand	1,000

Million		1,000,000

Billion		1,000,000,000


e.g.

two thousand = 2,000.





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