In a 10 m2 ecosystem, there are 20 raccoons. the population density of raccoons is

The answer is 2 raccoons per square meter.

The math is very clear. It can be solved using proportion.

If 20 raccoons live in 10 square meters, how many of them will live in 1 square meter:

20 raccoons : 10 m² = x raccoons : 1 m²

⇒ 

⇒ x = 

⇒ x = 2

So, a population density is 2 raccoons per square meter.

a- all cells come from pre-existing cells