Question

The disc jockey for the school dance charges $100 per hour for 3 hours plus $50 for each additional 20 minutes. If the disc jockey sends a bill for $450, how many additional minutes did the disc jockey continue to play the first 3 hours?

Answer 1

You can change the words into an equation:

300 + 50m = 450

The 300 is the charge for the first three hours 100 x 3

The m represents a 20 minute block of time. If you multiply $50 by the number of 20 minute blocks and add 300, you will get 450.

Solving for m will give you the number of 20 minute blocks. Then to find the number of minutes, just multiply by 20.