Flag of Qatar — construction sheet
Own work. Geometry from on Law No. (14) of 2012.
On this construction sheet, the length of the flag has been assigned a unitless value of 12600 which is not part of the government specification. The number 12600 has been chosen because it allows all given dimensions to be expressed as whole numbers.
The vertical line running though the middle of the sawtooth wave does not appear on the referenced source material.  It is located at exactly 1⁄3 of the flag's length from the hoist.

It is hopefully apparent that the area of the white part of the flag is exactly 1⁄3 of the total area of the flag.
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