Numbers expressed in scientific notation follow the general form
#color(blue)(a * 10^b)" "#, where
In your case, the mantissa is equal to
To convert this number from scientific notation to standard notation you need to move the decimal point to the right because you're dealing with a positive exponent.
As you move the decimal point to the right, you decrease the exponent by
This means that you would get
#6.3 * 10^(2) -> 63 * 10^1 -> 630 * 1 = 630#
The standard notation for