Problem: The amount of gasoline in a car tank follows a uniform distribution with a minimum of 1 gallon and a maximum of 12 gallons in the tank. ( The owner refills the car with gas when there is exactly one gallon left in tank) Provide your rationale and any supporting data.
Required:
a. What percentage of time will the car have over 9 gallons in the tank?
b. Given that there are at least 6 gallons left the tank, find the probability the car has at least 9 gallons left?