The total land area of the world is about fifty-seven million, two hundred eighty thousand square miles is 57, 280, 000 square miles
<em><u>Solution:</u></em>
Given that, we have to write the given words in number
The total land area of the world is about fifty-seven million, two hundred eighty thousand square miles
The number of zeros in million is 6
Here given that 57 million
So, 57 million means 57, followed by 6 digits
two hundred eighty thousand means 280 followed by 3 zeros
two hundred eighty thousand = 280 thousand
Thus the number is: 57, 280, 000