Question

The total cost of building a wall around a rectangular field is 680 at the rate of 8.5 per metre. If the length
of the field is 25 m, what is the breadth of the field?
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Answer 1

The breadth of the field is 15 m

Step-by-step explanation:

Let the breadth of the rectangular field is b m

Then the perimeter of the field is

= 2 (25 + b) m, where the length is 25 m

= (50 + 2b) m

At the rate of Rs. 8.5 per metre, the cost of building the wall around the field be

= Rs. (50 + 2b) × 8.5

= Rs. ( 425 + 17b)

According to the question,

425 + 17b = 680

or, 17b = 255

or, b = 15

Therefore the breadth of the field is 15 m