achloes wrote:
KarishmaB wrote:
jrzayev001 wrote:
If a certain grove consists of 36 pecan trees, what was the yield per tree last year?
(1) The yield per tree for the 18 trees in the northern
half of the grove was 60 kilograms last year.
(2) The yield per tree for the 18 trees in the eastern
half of the grove was 55 kilograms last year.
So the grove is split two ways into Northern half-Southern half and Western half-Eastern half. Think of a circle split horizontally into 2 parts and also vertically into two parts.
Using both statements, we know that there are 18 trees in the northern half so there must be 18 in the southern half. We also know that there are 18 trees in the eastern half and so there must be 18 in the western half.
For ease, let's assume each quadrant has 9 trees.
Attachment:
Ques3.jpg
The average yield in the northern half is 60 and average yield in the eastern half is 55. Note that 9 trees (in red) overlap in northern and eastern halves. We have no idea about the yield of the south west quadrant. Hence this is certainly not sufficient. Also, we don't know how many trees actually overlap and the yield of those trees.
Answer (E)
KarishmaB I marked C as it seemed to me that we have been given info on 100% of the trees and therefore we're able to calculate the yield per tree.
So here's my question: the statements clearly split the grove into two halfs, so I'm not sure why do we need to assume 4 quadrants. In which case, why are we not assuming 8 or 16 quadrants?
We can cut the grove into as many sections as we wish.
But when they talk about the Northern half, what is left? The southern half is left. So they have split the grove into two - northern half and southern half.
When we talk about the eastern half, what is left? The western half. So they have split the grove into two halves again but in a different way this time.
When we are given information about the northern half and the eastern half, we know for sure that we are not given anything about the south west part.
We know nothing about the trees that belong to the south-west part and to show that easily, we have split the grove into 4.