Question

A resting adult requires about 240mL of pure oxygen/min and breathes about 12 times every minute. If inhaled air contains 20 percent oxygen by volume and exhaled air 16 percent, what is the volume of air per breath? (Assume that the volume of inhaled air is equal to that of exhaled air).

How do i do this?

Answer 1

here we are again :) tell me if i did some bad math

Answer 2

20% air content inhaled -16% exhaled means the body absorbs 4% per breath.

12 breaths per minute yeild 240mL of total oxygen

Each breath is 20 mL
4% of the total volume of the breath is Oxygen.

4% = 20mL
so 20ml/.04 = 500mL per breath

1/2 a Liter per breath is the volume.

Answer 3

correct