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There are $$8$$ standing in a straight line. The first student is at the start of the line, and the last student is at the end of the line. The distance between each student is $$2$$ meters. How long is the line? (Ignore the thickness of the trees.) 
Overseas Competition->Knowledge Point->Word Problem Modules->Interval Problems
There are $7$ intervals between the first student and the last student. Thus, the line is $7 \times2 = 14$ meters long. 