The classic way to convey the error that exists in a measurement is a formula that shows the obtained measurement (X) as a sum of a true score plus some error. One version of this formula is: X = T + e. With this formula in mind, obtaining more precise measures depends on reducing error.
  Mega is the prefix meaning one million, therefore there are one million (1,000,000) gallons in a mega gallon.
The United States consumes 2.4822 gallons of oil per day per capita while Philippines consumes 0.1218. This entry is the total oil consumed in gallons per day (gal/day) divided by the population.