A farmer near Quiz Master Shop Towers was fencing one of his fields the other day. Very oddly, the field is an exact square, but we did not discuss why that might be. We instead talked about the very high-quality job that he had done so far and how economical his fencing solution was.
He had fenced three sides of the field and was going to drive to the hardware store to get the materials that he needed to complete the fence (apparently there wasn't enough wood in stock when he first went).
He divulged that he had spent £280 on the fence so far, which was three complete sides and the four corner posts. He told me that the corner posts had been £10 each, but he could not remember the cost of the fencing. And he was very vague about the size of the field, surprisingly so for a farmer.
How much should he expect to pay for the materials to complete the fence?
We know that the corner posts are £10 each and there are four of them, so the corners have cost a total of £40.
The farmer has spent a total of £280 on three sides and the corners, so the three sides must have cost £240. And each side must have cost £80.
The farmer needs one more side to complete the field and so can expect to pay a further £80.
Oddly we don't need to know the size of the field or the cost of fencing.
Even odder is why there is no gate to the field!