Ramesh wishes to fence a rectangular farm of 2000m 2 area in which len...
l*b = 2000
2b+l = 130
l = 50 b= 40
cost of fencing three sides = 130*3 = 390
cost of fencing four sides = 180*3 = 540
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Ramesh wishes to fence a rectangular farm of 2000m 2 area in which len...
To solve this problem, let's break it down step by step:
Given Information:
- Area of the rectangular farm = 2000m^2
- Length is greater than breadth
- Ramesh used 130m of wire to fence the farm on three sides
- Cost of 1m wire = Rs.3
Step 1: Finding the dimensions of the rectangular farm
Since the area of the rectangular farm is given as 2000m^2, we need to find the dimensions (length and breadth) that satisfy this condition.
Let's assume the length of the rectangular farm is L and the breadth is B.
According to the given condition, L > B.
Now, we can write the equation for the area of the rectangular farm:
L * B = 2000
Step 2: Finding the perimeter of the rectangular farm
To find the least length of wire required to fence the farm on three sides, we need to find the perimeter of the rectangular farm.
The perimeter of the rectangular farm is given by:
Perimeter = 2 * (Length + Breadth)
Since Ramesh used 130m of wire to fence the farm on three sides, we can write the equation:
2 * (L + B) = 130
Step 3: Solving the equations
Now, we have two equations:
L * B = 2000
2 * (L + B) = 130
We can solve these equations simultaneously to find the values of L and B.
Let's solve the second equation for L:
L = (130 - 2B) / 2
Substituting this value in the first equation:
[(130 - 2B) / 2] * B = 2000
Simplifying the equation:
130B - 2B^2 = 4000
2B^2 - 130B + 4000 = 0
Solving this quadratic equation, we get two values for B: B = 25 or B = 32
Step 4: Finding the least length of wire
Since we need to find the least length of wire, we will choose the smaller value of B, which is 25.
Substituting this value in the second equation:
2 * (L + 25) = 130
L + 25 = 65
L = 40
So, the dimensions of the rectangular farm are L = 40 and B = 25.
Step 5: Calculating the difference in cost
Now, let's calculate the cost of fencing the four sides of the rectangular farm.
The perimeter of the rectangular farm is:
Perimeter = 2 * (Length + Breadth) = 2 * (40 + 25) = 2 * 65 = 130m
Since the cost of 1m wire is Rs.3, the total cost of fencing the four sides would be:
Cost = Perimeter * Cost of 1m wire = 130 * 3 = Rs.390
The difference in cost between fencing three sides and four sides is:
Difference = Cost of fencing four sides - Cost of fencing three sides
Difference = Rs.390 - Rs.130 = Rs.260
Therefore, the correct answer is option 'B', Rs.150.