Final answer:
To find the cost of erecting a fence around a square field, calculate the perimeter of the field and multiply it by the cost per meter of fencing.
Step-by-step explanation:
To find the cost of erecting a fence around a square field, we need to calculate the perimeter of the field and then multiply it by the cost per meter of fencing.
Given that the area of the square field is 9 hectares, we can find the length of one side of the square by taking the square root of the area. The area of 9 hectares is equivalent to 90000 square meters. Taking the square root of 90000 gives us 300 meters.
The perimeter of the square field is found by multiplying the length of one side by 4. In this case, the perimeter is 300 meters * 4 = 1200 meters.
Finally, we can calculate the cost of erecting the fence by multiplying the perimeter by the cost per meter of fencing. In this case, the cost would be 1200 meters * 3.50/- = 4200/-. Therefore, the cost of erecting the fence around the square field is 4200/-.