Suppose the residents of Mediaville spend all of their income on books, CDs, and DVDs.
In 2009, they buy 400 books for $3, 200 CDs for $1,400, and 100 DVDs for $900.
In 2010, they buy 360 books for $3, 240, 250 CDs for $1,500, and 125 DVDs for $1,250. Assume that the market basket for the CPI is defined in the base year.
Using 2009 as the base year, what is the inflation rate in 2010?