Dividing 1 by powers of ten

Question

I have something like, say, 3.9 x 10^-22 and I want it to be divided by 1. This is common in Chemistry science questions, but I fail to get the thing. How can we divide 1 by 3.9 x 10^-22 and get a proper answer? I mean, I get confused. Thank you for any help.

Answer 1

$\dfrac{1}{3.9\times 10^{-22}} = \dfrac{1}{3.9}\times \dfrac{1}{10^{-22}} \approx 0.256\times 10^{22} = 2.56\times 10^{21}$, if you want the answer to be in scientific notation.