sparkles3144 wrote:Sue planted 4 times as many apple seeds as she planted orange seeds. 15 percent of the apple seeds grew into trees, and 10 percent of the orange seeds grew into trees. If a total of 420 apple trees and orange trees grew from the seeds, how many orange seeds did Sue plant?
A. 540
B. 600
C. 660
D. 720
E. 760
We can PLUG IN THE ANSWERS, which represent the number of orange seeds planted.
When the correct answer choice is plugged in, the total number of trees will be 420.
D: 720
Since 10% of these 720 orange seeds grow into trees, the number of orange trees = 10% of 720 = 72.
Since 4 times as many apple seeds as orange seeds are planted, the number of apple seeds planted = 4*720 = 2880.
Since 15% of these 2880 apple seeds grow into trees, the number of apple trees = 15% of 2880 = 432.
Total number of trees = 72+432 = 504.
Too many trees.
Since the correct answer choice must be SMALLER, eliminate D and E.
B: 600
Since 10% of these 600 orange seeds grow into trees, the number of orange trees = 10% of 600 = 60.
Since 4 times as many apple seeds as orange seeds are planted, the number of apple seeds planted = 4*600 = 2400.
Since 15% of these 2400 apple seeds grow into trees, the number of apple trees = 15% of 2400 = 360.
Total number of trees = 60+360 = 420.
Success!
The correct answer is
B.
Sue planted 4 times as many apple seeds as she planted orange seeds.
Meaning:
For every orange seed planted, 4 apple seeds are planted.
Thus:
O/A = 1/4
A = 4O.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at
[email protected].
Student Review #1
Student Review #2
Student Review #3
