I've come across a government document on a profile of a city, and have been curios to how to solve for this or if there's already a named formula for it.
City X
- Land Area: 49800 ha .
- Alienable Area: 1,883.21 ha., which is 3.78% of 49800
Now, one barangay(smallest administrative division in the Philippines) of the city has the following data.
Barangay A
- Land Area: 11332 ha., which is 22.76% of 49800
Is it possible for me to compute the alienable area of Barangay A using the Alienable Area of the City along with the Land Area of Barangay A?
The best you can do here is use simple unitary method. This assumes that the Alienable area is spread uniformly across the City X.
So if $1883.21$ ha of Alienable land is present in $49800$ ha, then the city of Barangay contains:
$$\frac{1883.21}{49800} \times {11332}\text{ ha}$$
Alienable land.