Difficulty: Fun
Sergio is an electrician repairing a power line. There’s a stretch of eight, evenly spaced power poles he’s working on. The distance from the first to the fourth is 120 metres. What’s the distance from the first to the eighth pole?
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Brainteaser hint
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Brainteaser answer
Since the poles are evenly spaced, the gaps between them are the same.
Between the first and fourth poles, there are three gaps (1–2, 2–3, 3–4). It’s 120 metres for three gaps, so each gap is 40 metres (120 / 3 = 40).
There are seven gaps between the first and eighth poles. That means the distance between them must be 7 x 40 = 280 metres!
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