Description: Inequalities are more than abstract concepts and exercises. They help solve real life problems. Here's an example. Created by Sal Khan and Monterey Institute for Technology and Education. A contractor is purchasing some stone tiles for a new patio. Each tile costs $3, and he wants to spend less than $1,000. Write an inequality that represents the number of tiles he can purchase with a $1,000 limit.*Teacher Advisor is 100% free.