farm A&B

[AIM TO CRACK GMAT]

Farm A had an average output of 300 kgs of wheat per acre. Farm B had an average output of 350 kgs of wheat per acre. It is known that Farm B's area is 15 acres less than Farm A's. It is also known that Farm B in total harvested 2000 kgs of wheat more than Farm A. What is the area of Farm A?


(A)130 acres (B) 135 acres (C) 145 acres (D)160 acres

OA C

[mevicks]

35

Farm A had an average output of 300 kgs of wheat per acre. Farm B had an average output of 350 kgs of wheat per acre. It is known that Farm B's area is 15 acres less than Farm A's. It is also known that Farm B in total harvested 2000 kgs of wheat more than Farm A. What is the area of Farm A?


(A)130 acres (B) 135 acres (C) 145 acres (D)160 acres

OA C

Farm A --> Let the area be x acres
Farm B --> area is (x - 15) acres

for x acres A's produce is 300x
for (x - 15) acres B's produce is 350(x - 15)

We are given that B's produce is 2000 more than that of A's:
350(x - 15) = 300x + 2000
[spoiler]Answer : x = 145[/spoiler]

[Brent@GMATPrepNow]

Farm A had an average output of 300 kgs of wheat per acre. Farm B had an average output of 350 kgs of wheat per acre. It is known that Farm B's area is 15 acres less than Farm A's. It is also known that Farm B in total harvested 2000 kgs of wheat more than Farm A. What is the area of Farm A?

(A)130 acres
(B) 135 acres
(C) 145 acres
(D)160 acres

Let B = area of Farm B (in acres)

Farm B's area is 15 acres less than Farm A's
So, B + 15 = area of Farm A (in acres)

Farm B had an average output of 350 kgs of wheat per acre.
Farm B total output = 350B

Farm A had an average output of 300 kgs of wheat per acre.
Farm A total output = 300(B+15)

Farm B in total harvested 2000 kgs of wheat more than Farm A
In other words, (Farm B's total output) - (Farm A's total output) = 2000
We get: 350B - 300(B+15) = 2000
Expand: 350B - 300B - 4500 = 2000
Simplify: 50B = 6500
B = 130

What is the area of Farm A?
area of Farm A = B + 15
= 130 + 15
= 145
= C

Cheers,
Brent

[GMATGuruNY]

Farm A had an average output of 300 kgs of wheat per acre. Farm B had an average output of 350 kgs of wheat per acre. It is known that Farm B's area is 15 acres less than Farm A's. It is also known that Farm B in total harvested 2000 kgs of wheat more than Farm A. What is the area of Farm A?


(A)130 acres (B) 135 acres (C) 145 acres (D)160 acres

OA C

An alternate approach is to plug in the answers, which represent the area of Farm A.
The area of Farm B is 15 acres less than that of Farm A.

Answer choice B: A = 135 acres, B = 120 acres
Since A produces 300kg per acre, A's output = 300*135 = 40500kg
Since B produces 350kg per acre, B's output = 350*120 = 42000kg.
B-A = 42000-40500 = 1500kg.
Since the required difference -- 2000kg -- is GREATER than 1500, try a BIGGER answer choice.

Answer choice C: A = 145 acres, B = 130 acres
Since A produces 300kg per acre, A's output = 300*145 = 43500kg
Since B produces 350kg per acre, B's output = 350*130 = 45500kg.
B-A = 45500-43500 = 2000kg.
Success!

The correct answer is C.

[sahilchaudhary]

IMO C.