Double Square Foot (abbreviation: ft4): is an imperial unit and U.S. customary unit (non-SI, non-metric) of area moment of inertia, a geometrical property of an area which reflects how its points are distributed with regard to an arbitrary axis.
Double Square Millimeter (abbreviations: mm4, or mm 4): is the SI derived unit of area moment of inertia, a geometrical property of an area which reflects how its points are distributed with regard to an arbitrary axis.
How to Convert Double Square Feet to Double Square Millimeters
Example: How many double square millimeters are equivalent to 39.12 double square feet?
As;
1 double square feet = 8630974841.2416 double square millimeters
39.12 double square feet = Y double square millimeters
Assuming Y is the answer, and by criss-cross principle;
Y equals 39.12 times 8630974841.2416 over 1
(i.e.) Y = 39.12 * 8630974841.2416 / 1 = 337643735789.37 double square millimeters
Answer is: 337643735789.37 double square millimeters are equivalent to 39.12 double square feet.
Practice Question: Convert the following units into mm4:
N.B.: After working out the answer to each of the next questions, click adjacent button to see the correct answer.
( i ) 89.23 ft4
( ii ) 48.46 ft4
( iii ) 47.95 ft4