a payday loan store charges $30 for a one-month loan of $600. What is the annual interest rate is this equivalent to ?

Finding what percentage is $30 of $600:
[tex] \frac{30}{600} \times100=5\%[/tex]
So, it is 5% per month.

Converting it to annual:
[tex]5\%\times 12=60\%[/tex]