00:01
In a forest, four sevenths of the trees are conifer and the rest are leaf bearing.
00:05
Among the leaf -bearing trees, 7 .15th are oak and two -thirds of these oaks are new.
00:11
There are 160 old oaks in the forest.
00:14
How many trees are in the forest? so let's fill in some of the missing information.
00:21
If we know four -sevenths are conifers, then we know that three -sevenths are leaf -bearing.
00:26
If we know that two -thirds are new, we know that one -third are old.
00:32
We know 7 .15s are oaks, then we know that 8 .15s are not oaks.
00:38
So we know that for now.
00:41
So let's see what we know.
00:42
We know 160 old oaks.
00:45
That's going to be this one -third of the oak trees.
00:49
So the question is, how can we get this in terms of all the trees and not just the old oak trees? and that's what we're going to start out with all these other fractions.
01:03
To do that, let's start with a larger category.
01:06
We're going to go start with three -sevenths.
01:09
Three -sevenths of the trees are leaf -berrying...