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
Answer is B
Shouldn't the ratio of apple:orange be 4:1 or 4A=O?
I didn't understand Mangoosh's explanation
Planting Seeds. Mangoosh Question
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The equation would actually be A=4O. There are more apples, so you need to increase the orange count to make them equal.
.15A + .1O = 420
A=4O
_______________
(.15)(4O) + .1O = 420
.7O = 420
O = 600
.15A + .1O = 420
A=4O
_______________
(.15)(4O) + .1O = 420
.7O = 420
O = 600
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We can PLUG IN THE ANSWERS, which represent the number of orange seeds planted.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
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.
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We can also solve the question using ONE VARIABLEsparkles3144 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
Let x = # of orange seeds planted
Sue planted 4 times as many apple seeds as she planted orange seeds
So, 4x = # of apple seeds planted
15 percent of the apple seeds grew into trees, and 10 percent of the orange seeds grew into trees.
So, 0.15(4x) = number of apple trees that developed
And 0.1(x) = number of orange trees that developed
A total of 420 apple trees and orange trees grew from the seeds
We get: 0.15(4x) + 0.1(x) = 420
Simplify: 0.6x + 0.1x = 420
Simplify: 0.7x = 420
Solve: x = 600
Answer: B
Cheers,
Brent