Bunuel wrote:

In a forest, the ratio of pine trees to maple trees if 7:3, and the ratio of oak trees to maple trees is 5:2. What is the ratio of pine trees to oak trees?

A. 7:5

B. 5:7

C. 7:10

D. 14:15

E. 15:14

We are given that the ratio of pine trees to maple trees is 7:3 and that the ratio of oak trees to maple trees is 5:2. Thus:

pine trees : maple trees = 7 : 3

and

oak trees : maple trees = 5 : 2

We can manipulate the first ratio by multiplying by 2 and we have:

pine trees : maple trees = 14 : 6

We can manipulate the second ratio by multiplying by 3 and we have:

oak trees : maple trees = 15 : 6

Thus, the ratio of pine trees to oak trees is 14 : 15.

Answer: D

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