A sample of air has a volume of 140.0 mL at 67C. To w

hat temperature must the gas

be lowered to reduce its volume to 50.0 mL at constant pressure?

What that means is that when pressure and number of moles are kept constant, increasing the temperature will result in an increase in volume. Likewise, a decrease in temperature will result in a decrease in volume. In your case, the volume of the gas decreased by a factor of about 3, from "140.0 mL" to "50.0 mL".