Then to get it back in standard form, you need the first bit to look like "X.XX", so re-write 22.72x10^3 as 2.272x10^4. Note that you divide the first bit by ten and then raise the exponent by one.
The same method can be applied for the second method. Give it a go. (remember 1/(x^a) == x^(-a), i.e. the exponent sign goes negative when you move from denominator to numerator)