A person who exercises vigorously several hours a day might take in about 22 m3 of air per day. A tree about 33 m tall and 0.55 m in diameter at its base produces about 84,000 L of oxygen per year. How many people, breathing as described this way, would five such trees supply with oxygen? (Please recall, that 1 m3 = 1000 L, and that normally there's about 20% of oxygen in the air around.)

95 people can breath with five such trees supplying oxygen.

Explanation:

Given data:

a man take in oxygen in a day : 22 (1 = 1000L)

Tree length: 33 m

Tree diameter : 0.55 m

tree produce oxygen in a year : 84,000 L

Tree oxygen in the air : 20%

1 = 1000 L

To find:

number of people can breath with 5 such trees:  ?

Calculation:

Calculate the oxygen produced by 5 trees:

= 5 x 84,000

= 420.000 L

= 420

Calculate the air

= 420 x 100% / 20%

= 2100 m^3

Calculate the number of people:

= 2100 m^3 / 22 m^3

= 95.5

= 95 people

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