500
This is a Scientific Notation Problem....
Recently in the US, there were about 300,000,000 cell phone users. That same year, there were 5.7 x 10^9 cell phone users worldwide. About how many times larger was the number of cell phone users worldwide than in the US?
What is 19 times larger?
How? This is a division problem. Set it up how the problem asks: Worldwide users/US users.
5.7 x 10^9 divided by 300,000,000 (3 x 10^8)
Now follow the rules. (5.7 / 3) and Subtract Exponent (9-8)
= 1.9 x 10 (to the first power). = 19