The only thing that stopped you from finishing was a lack of ambition.
The test is about what the teacher taught the student. What is the cost of a square farm at $15 per acre, the distance around which is 640 rods?
First, it tells you the farm is square. It also tells you the distance around the square farm is 640 rods, which means the farm has four 160 rod long sides. Therefore, a rod must be a measure of distance. Today, as then, an acre is a measure of land equaling 160 square rods, 10 square chains, 4,840 square yards, 43,560 square feet, or 0.405 hectares. Today, as then, a rod is a linear measure equal to 5.5 yards or 16.5 feet (5.03 meters). Also called pole.
Would it be easier for you if the question were more modern? What is the cost of a square farm at $15 $4,500.00 per acre, the distance around which is 640 rods 10,650 feet?
The most striking concept of this test is that in order for it to be graded the teacher would actually have to read the students’ answers. The teacher would be able to discern a student's thought process in his answer. What a novel idea.
My comment was that I could do the math part if I understood what the units used meant. That is something that I could look up on Wikipedia.