A company manufactures two types of custom-designed furniture: chairs and tables. Each chair requires $c$ hours of labor to build, and each table requires $t$ hours of labor to build. The total labor available for a specific project is 360 hours. The relationship between the number of chairs ($x$) and the number of tables ($y$) that can be built with the available labor is represented by a line on a coordinate plane. This line passes through the points $(45,0)$ and $(0,30)$. If the company decides to build 15 chairs, how many tables can they build with the remaining labor hours?