An unusually severe increase in gasoline prices may have motivated full-sized pickup truck buyers to purchase a highly fuel-efficient vehicle. Purchase behavior was collected in one area for one year and reported below.

1. Complete the row and column totals. What is the independent variable?

   Hint (a):

   The price of gas influences the number of fuel efficient
   cars purchased, not the other way around.

   Partial Answer (a):

   Fuel price is the independent variable.

2. Create a conditional relative frequency table. Is there an association between fuel prices and the number of highly fuel-efficient trucks purchased?

   Hint (b):

   Since fuel price is your independent variable, use the column totals to determine conditional relative frequencies.

   Partial Answer (b):

   	Low Fuel Prices	High Fuel Prices
   Number of Highly Fuel Efficient Trucks Purchased	1.1%
   Number of Ordinary Cars and Regular Trucks Purchased		99.0%