Fractions/Ratios/Decimals

[swerve]

In a forest, the ratio of pine trees to maple trees is 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

The OA is D

Source: Veritas Prep

[Jay@ManhattanReview]

In a forest, the ratio of pine trees to maple trees is 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

The OA is D

Source: Veritas Prep

So, we are given that p/m = 7/3 and o/m = 5/2

Since we have to find out the value of p/o, we must have the ratio value of 'm' unique for the ratios p/m and o/m.

We see that for p/m, the ratio value of m is 3 and that for o/m is 2, so let's make it 6 (LCM of 3 and 2).

=> p/m = 14/6 and o/m = 15/6 => p/o = 14/15

Correct answer: D

Hope this helps!

-Jay
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[Scott@TargetTestPrep]

In a forest, the ratio of pine trees to maple trees is 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

The OA is D

Solution:

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