Question

A single tree produces about 2.6 × 102 lb of oxygen each year. The Amazon rainforest has about 3.9 × 1011 trees.



About how many ounces of oxygen are produced in the rainforest each day ?



4.4 × 10 ( answer ) oz

Answer 1

So, for this, you've got an initial unit (2.6x102) in lb, where you need ounces
Using the method of crossing, we find that 2.6x102x8 will get you the right answer.
Before I continue, why are these in multiplication problems, rather than straight numbers?

Answer 2

not sure what that means , but it's actually 2.6 x 10^2 lb and 3.9 x 10^11 trees

Answer 3

Oh, okay, scientific notation. So, essentially 260 lbs x 8
390000000000 trees, which is why it's 3.9x10^11
So, that will get you the amount of oxygen in the forest

Answer 4

ok thanks