The strauss insurance company laid off 20% of its employees one year and then increased its staff by 12 1/2% the following year. if the firm originally employed 120 workers, what was the net change in staff over two-year period?

take the logarithm of both sides (the base of the log doesn't matter):

apply the exponent property - this says that :

distribute the log terms on both sides:

group like terms together:

divide through both sides by the coefficient on :

you can do some additional rewriting here using the properties of the logarithm to simplify things if you like: