How much oxygen does a person consume in a day?

The average adult, when resting, inhales and exhales about 7 or 8 litres of air per minute.That totals about 11000 litres of air per day.Inhaled air is 20% oxygen and nearly 15% is exhaled.Therefore a human consumes about 550 litres of pure oxygen per day, Based on a market survey. We found that the average cost of a 2.75 litre portable oxygen cylinder is Rs.6500. At this rate, a human consumes oxygen worth about Rs.13 lakhs per day.

DIFFERENT CALCULATIONS:

"A mature leafy tree produces as much oxygen in a season as 10 people inhale in a year." "A single mature tree can absorb carbon dioxide at a rate of 48 pounds/year and release enough oxygen back into the atmosphere to support two human beings." "One acre of trees annually consumes the amount of carbon dioxide equivalent to that produced by driving an average car for 42,000 kms. That same acre of trees also produces enough oxygen for 18 people to breathe for a year.” "On average, one tree produces nearly 260 pounds of oxygen each year. Two mature trees can provide enough oxygen for a family of four."