Answer:
Surface area of Earth = 499.8677053 * 10^6 square kilometers
Step-by-step explanation:
From the basics of conversion, we can find that:
1 mile is equivalent to 1.609344 km
Therefore:
1 square mile is equivalent to (1.609344)^2 = 2.58998811 square kilometers
Now, we are given that the surface area of earth is 193 million square miles. To know its equivalence in square km, all we have to do is cross multiplication as follows:
1 square mile ...................> 2.58998811 square kilometers
193 * 10^6 square miles ...> ?? square km
Area = (193 * 10^6 * 2.58998811) / (1)
Area = 499.8677053 * 10^6 square km
Hope this helps :)