Originally Posted by

**Dougster** Would you be able to simplify the middle of your reply into what buttons to press on the calculator.

I guess the answer may depend on what sort of calculator you have. I use an ancient Casio. If I want to find $\displaystyle \frac{\log0.4}{\log2}$ then I press these buttons:

$\displaystyle \boxed{\mathstrut 0.4}\quad \boxed{\mathstrut \log}\quad \boxed{\mathstrut \div}\quad \boxed{\mathstrut 2}\quad \boxed{\mathstrut \log}\quad \boxed{\mathstrut =}$.

In that sequence, "log" means log to the base 10. You can replace both "log"s by "ln" (natural log, or log to base e), and the result will be the same.

Caution. Your results may vary. Different calculators use different sequences of operations.