To subtract numbers written in scientific notation, we need to make sure that the exponents are the same. In this case, we have (5.3 x 10^8) - (8.2 x 10^6).
To make the exponents the same, we can rewrite 8.2 x 10^6 as 0.082 x 10^8. This doesn't change the value, but it helps us compare the exponents.
Now we can subtract the numbers: (5.3 - 0.082) x 10^8 = 5.218 x 10^8.
Therefore, the answer is 5.218 x 10^8.
Note: It's important to remember to keep the same exponent when subtracting numbers in scientific notation. By rewriting 8.2 x 10^6 as 0.082 x 10^8, we made the exponents the same so we could subtract the numbers correctly.