A rectangular savannah is 30m long by 15m wide. The Ministry of Education wants to fence that savannah using posts and wire. If the posts, costing $18.00 each, are placed 5m apart andt the wire cost $35.00 per metre. Calculate the cost of the posts and wire for fencing that savannah.
Draw a diagram placing the posts. How many posts are needed?
Six posts are on one side. What about the other three sides?
Did you draw a diagram?
18 posts
Right.
The cost of the posts:
18 * 18 = ?
How much wire is needed?
15X 35 =525 x2 = 1050
30X 35 = 1050 x 2 = 2100
total cost of wire = $3,150
Where did you get those numbers?
Your answer us right, but impossible to get with your figures.
P = 2L + 2W
P = (2 * 30) + (2 * 15)
P = 90 meters
Cost of wire = 90 * 35
To calculate the cost of the posts and wire for fencing the rectangular savannah, we need to find the total perimeter of the rectangle and then calculate the cost based on the given prices.
The perimeter of a rectangle is calculated by adding the lengths of all four sides. In this case, the length of the rectangle is 30m and the width is 15m.
The total perimeter (P) is calculated as follows:
P = 2L + 2W
Substituting the values, we get:
P = 2(30) + 2(15)
P = 60 + 30
P = 90m
The cost of the posts is $18.00 each, and they are placed 5m apart. This means we need (P/5) + 1 posts, as there will be one post at each end and then one post every 5m.
Substituting the value of P, we get:
Number of posts = (90/5) + 1
Number of posts = 18 + 1
Number of posts = 19
Therefore, the cost of the posts is 19 * $18.00 = $342.00.
The cost of the wire is $35.00 per meter. To find the required length of wire, we use the perimeter of the rectangle, which we calculated as 90m.
Therefore, the cost of the wire is 90 * $35.00 = $3,150.00.
Finally, to find the total cost, we need to add the cost of the posts and the cost of the wire:
Total cost = Cost of posts + Cost of wire
Total cost = $342.00 + $3,150.00
Total cost = $3,492.00.
Therefore, the cost of the posts and wire for fencing the rectangular savannah is $3,492.00.