6.6 is close to 7 so we round it there. 10 to the power of 7 is 10 million so 7 x 10 million is 70 million. Now let’s look at United States. 3.19 is close to 3 so we round it there. 10 to the power of 8 is 100 million. 3 x 100 million is 300 million now we subtract 300 million with 70 million and that is 230 million.
Hope this helps!