Suppose that a state has increased its sales tax rate every other year since 2005. Assume the state collected all sales taxes that residents legally owed. The table below summarizes its experience. What were total taxable sales in this state during each year displayed in the table?
Year _________Sales Tax Rate _______Sales Tax Collections
2005 ............. 0.03 (3 percent) ..................... $9.0 million
2007 ............ 0.04 (4 percent) ..................... $14.0 million
2009 ............ 0.05 (5 percent) ..................... $20.0 million
2011 ............ 0.06 (6 percent) ..................... $24.0 million
2013 ............ 0.07 (7 percent) ..................... $29.4 million