How Do You Express a Logarithm in Terms of Common Logarithms?

Logarithms can be a little tricky and if you'd like to use a calculator you'll need to use a formula to change the given logarithm into base ten. This tutorial defines the formula, uses it to change a logarithm to base ten, then how to use the new logarithm in a calculator to determine an answer. Wow, now that's a helpful tip!