This is a fantastic problem that draws from multiple concepts and abilities, yet is entirely approachable.
If your students are learning scale factor and conversion between units, this is a fantastic problem.
There are notes at the bottom of the slides that will help guide you through the lesson.
Please feel free to contact me with comments or concerns at: firstname.lastname@example.org
For other lessons and math topics, please visit: http://thebeardedmathman.com