The cows of Argentina needs an approximate area of 4200 m² for grazing, and there is a total of 4500 cows.
And we are asked to find the total area of their grazing but in hectares. So, we can write:
![1 \: cow = 4200 \: {m}^{2}](https://tex.z-dn.net/?f=1%20%5C%3A%20cow%20%3D%204200%20%5C%3A%20%20%7Bm%7D%5E%7B2%7D%20)
Then, for 4500 cows:
![4500 \: cows = 4200 \: {m}^{2} \times 4500](https://tex.z-dn.net/?f=4500%20%5C%3A%20cows%20%3D%204200%20%5C%3A%20%20%7Bm%7D%5E%7B2%7D%20%20%5Ctimes%204500)
![4500 \: cows = 18900000 \: m {}^{2}](https://tex.z-dn.net/?f=4500%20%5C%3A%20cows%20%3D%2018900000%20%5C%3A%20m%20%7B%7D%5E%7B2%7D%20)
We know that, 1 hectares = 10000 m² = 10⁴ m²
Then let the area of the field be x in hectares:
![1 \: hectare = 10000 \: {m}^{2}](https://tex.z-dn.net/?f=1%20%5C%3A%20hectare%20%3D%2010000%20%5C%3A%20%20%7Bm%7D%5E%7B2%7D%20)
![x \: hectare = 18900000 \: {m}^{2}](https://tex.z-dn.net/?f=x%20%5C%3A%20hectare%20%3D%2018900000%20%5C%3A%20%20%7Bm%7D%5E%7B2%7D%20)
Then, putting them in proportion, We will get:
![x = \dfrac{18900000}{10000} hectares](https://tex.z-dn.net/?f=x%20%3D%20%20%5Cdfrac%7B18900000%7D%7B10000%7D%20hectares)
![x = \boxed{ 1890 \: hectares}](https://tex.z-dn.net/?f=x%20%3D%20%20%5Cboxed%7B%201890%20%5C%3A%20hectares%7D)
So, the total area in hectares = <u>1</u><u>8</u><u>9</u><u>0</u><u> </u><u>hectares</u><u>.</u>
And we are done !!
#CarryOnLearning
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