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Farmers Field

Stage: 3 Challenge Level: Challenge Level:1

Phil of Westwood High School, Leek, Staffordshire wrote:
 

The problem called farmers fields in the 15+ challenges can be proven wrong, the shortest wall isn't always a straight line.Consider this field: -

If the left side is slightly larger than the right side then the shortest distance to build the wall could be to use a curve as shown by the red line (A).To use straight lines would involve using three if placed as shown by the green lines (B), or two straight lines could be used as shown by the purple line (C).

To use one straight line the shortest route would be as indicated by the blue line (D).It is obvious from looking that when the difference is very small that a single straight line won't be the shortest difference.