3) Simple geometry
The Swedish flag has a yellow cross of constant width in a blue background.
The yellow area represents one-third of the flag's area.
If the flag is 1m long and 66cm wide, what is the width of the yellow stripes ?
The stripes comprising the cross can be "moved" to the edges of the flag.
Let = width of the stripe (cm).
* - - - - - - - - *
| | x
| * - - - - - - *
66 | | |
| | | 66-x
| | |
* - * - - - - - - *
The blue region's area is: . cm²
It is also: . cm²
Hence, we have: .
The Quadratic Formula gives us: .
The smaller root is the answer: . cm.