A rectangular lot, 12 metres long and 8 metres wide, is to be enclosed by a fence with posts 4 metres apart. If each post costs $75.00, how much would be spent for all the post?
2006-12-27 23:33:33 · 9 answers · asked by Hybrid Angel 2 in Science & Mathematics ➔ Mathematics
The perimeter is 40 meters
Perimeter formula
P = 2L + 2W
P = 2(12) + 2(8)
P = 24 + 16
P = 40 Meters
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each post is 4 meters apart. divide 40 by 4
40 / 4 = 10
a total of 10 posts will be required to complete the perimeter.
The cost of each post is $ 75.00
Multiply 75.00 times 10 to obtain the total cost
75 x 10 = 750.00
The total cost of the posts is $ 750.00
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2006-12-27 23:42:42 · answer #1 · answered by SAMUEL D 7 · 0⤊ 0⤋
given: length=12m.; width=8m.
sol'n:
hmm... so if its rectangular then there posts 4 meters apart...
so 12/4=3.. since in a rectangle there is 2 lengths, then 3*2=6....
lets go to the width, 8/4=2, ang like length, there is two widths in a rectangle so,,, 2*2=4..
lets add it all up:
6+4=10...
so there are a total of 10 posts in the lot,
if each post costs $75.00...
then $75.00 x 10= $750.00
so the lot costs $750.00.... ^_^
or you could use another method by using perimeters..
in a rectangle, P=2L + 2W..
so... 2(12) + 2(8)... or 24 + 16= 40
since there are 4 m. gap in each post...
40/4=10....
and each post is $75.00...
10 x $75.00 = $750.00
the total cost is : $750.00
2006-12-28 07:49:23 · answer #2 · answered by maila_venus9193 2 · 0⤊ 0⤋
I think it's 10 posts or $750. Draw a diagram it's easier to see.
1 on each corner then 1 more on each of the 8 metre sides and 2 more on each of the 12 metre sides.
2006-12-28 07:45:05 · answer #3 · answered by reddy2hunt 4 · 0⤊ 0⤋
Perimeter = (2x12) + (2x8)
= 24 + 16
= 40 m
So the number of posts will be 40/4 = 10 posts
Cost = 75.00 x 10
= $750.00
2006-12-28 07:40:17 · answer #4 · answered by Anonymous · 0⤊ 0⤋
ight this one's easy.....
perimeter of plot= 2(12+8)
= 40
therefore, 40/4= 10(no. of posts)
1 post= $75
10posts=?
10 x 75/1 = 750
Ans. = $750
2006-12-28 07:45:15 · answer #5 · answered by Andrea 1 · 0⤊ 0⤋
an = a1 + (n - 1)r
40 = 0 + (n - 1)4
40 = 0 + 4n - 4
40 + 4 = 4n
4n = 44
n = 44/4
n = 11
Post costs = $75 x 11 = $825
Answer: It wold be spent for all the post $ 825.00.
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2006-12-28 19:22:19 · answer #6 · answered by aeiou 7 · 0⤊ 0⤋
A total of 10 posts at $75 apiece would be $750.00.
2006-12-28 07:43:36 · answer #7 · answered by Surveyor 5 · 0⤊ 0⤋
perimeter=2(l+b)
=2*20
40m
There are 10 posts because they are 4m part.
10*75= $750
2006-12-28 11:41:35 · answer #8 · answered by Nitin T F1 fan 5 · 0⤊ 0⤋
Let's start by setting up the lot on a rectangular coordinate axis. Put one post at (0,0). Then with long side along the x-axis and going out we would need a post at (4,0) , at (8,0) and at (12,0). Now going vertically we need a post (along the short side) at (12, 4) and at (12,8). Now going back horizontally we need a post at (8,8) , at (4,8) and at (0,8). And lastly going down vertically we need a post at (0,4) and at (0,0)/ BUT WE |ALREADY HAVE ONE AT (0,0), so forget the last one. Now count them up : (0,0), (4,0), (8,0), (12,0), (12,4), (12,8), (8,8), (8,4),
(8,0), (4,0). That is 10 posts. Simple isn't it. Always, Always, Always, try to visualize what you are doing and use whatever means necessaary to make the math involved easy to understand.
2006-12-28 07:55:47 · answer #9 · answered by ? 3 · 0⤊ 0⤋