A fence consists of m lengths of fence that are each n feet long. A fence post separates each length of fence by its width of x feet. What is the total length of the fence including the fence posts on each end?
A. mn
B. m(n + x)
C. m(n + x) + x
D. m(n +x) + 2x
E. 2mn
The OA is C.
The total length of fence without the posts would be mn, now if there are 2 fences would be 3 posts because PFPFP, so total posts = (n + 1). Length of the posts = (n+1)x. The total length of fence = nx + x + nm, therefore C is the correct answer.
Has anyone another strategic approach to solve this PS question? Regards!
A fence consists of m lengths of fence that are each n feet
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Hi All,
We're told that a fence consists of M lengths of fence that are each N feet long and a fence post separates each length of fence by its width of X feet. We're asked for the total length of the fence, including the fence posts on each end. This question can be solved by TESTing VALUES.
IF....
M=2, N=10, X=1....
Then we have 2 pieces of fence (at 10 feet each) and 3 posts (at 1 foot each)...
Total length = 20 + 3 = 23 feet
So we're looking for an answer that equals 23, when we plug in M=2, N=10, X=1....There's only one answer that matches....
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
We're told that a fence consists of M lengths of fence that are each N feet long and a fence post separates each length of fence by its width of X feet. We're asked for the total length of the fence, including the fence posts on each end. This question can be solved by TESTing VALUES.
IF....
M=2, N=10, X=1....
Then we have 2 pieces of fence (at 10 feet each) and 3 posts (at 1 foot each)...
Total length = 20 + 3 = 23 feet
So we're looking for an answer that equals 23, when we plug in M=2, N=10, X=1....There's only one answer that matches....
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
GMAT/MBA Expert
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AAPL wrote:A fence consists of m lengths of fence that are each n feet long. A fence post separates each length of fence by its width of x feet. What is the total length of the fence including the fence posts on each end?
A. mn
B. m(n + x)
C. m(n + x) + x
D. m(n +x) + 2x
E. 2mn
The total length of the fence only (without the posts) is mn feet long. Since each post is x feet long and there is a post at each end of the fence in addition to the posts separating each length of the fence, there must be (m + 1) posts along the fence. Thus the total length of the posts is x(m + 1), and the total length of the fence, including the posts, is:
mn + x(m + 1)
mn + xm + x
m(n + x) + x
Alternate Solution:
Let's suppose that there were m = 3 lengths of fence that are n = 2 feet long and the posts separating the fences were x = 1 foot. Under these assumptions, the total length is 1 + 2 + 1 + 2 + 1 + 2 + 1 = 10 feet. Let us see which answer choice(s) give us 10 when m = 3, n = 2 and x = 1:
Answer Choice A:
mn = 3(2) = 6
Eliminate answer choice A.
Answer Choice B:
m(n + x) = 3(2 + 1) = 9
Eliminate answer choice B.
Answer Choice C:
m(n + x) + x = 3(2 + 1) + 1 = 10
C is a possible choice.
Answer Choice D:
m(n + x) + 2x = 3(2 + 1) + 2 = 11
Eliminate answer choice D.
Answer Choice E:
2mn = 2(3)(2) = 12
Eliminate answer choice E.
The only possible answer choice is C.
Answer: C
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