When the Local Used Bookstore Prices Economics Books at $15

Multiple Choice

When the local used bookstore prices economics books at $15.00 each,they generally sell 70 books per month.If they lower the price to $7.00,sales increase to 90 books per month.Given this information,we know that the price elasticity of demand for economics books is about

A) 2.91, and an increase in price from $7.00 to $15.00 results in an increase in total revenue.
B) 2.91, and an increase in price from $7.00 to $15.00 results in a decrease in total revenue.
C) 0.34, and an increase in price from $7.00 to $15.00 results in an increase in total revenue.
D) 0.34, and an increase in price from $7.00 to $15.00 results in a decrease in total revenue.