Which is longer 5 miles or 10 kilometers?

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Answer 1 · 2016-11-03T23:21:14

#10# kilometers

#5# miles is about #8# kilometers, so #10# kilometers is longer.

The exact conversion figure is #1.609344#, which follows from one inch being defined as #2.54# cm

I find it handy to use the first few terms of the Fibonacci sequence as an approximation for converting between miles and kilometers.

The Fibonacci sequence starts #1, 1#. Then every subsequent term is formed by adding the two previous terms:

#1, 1, 2, 3, 5, 8, 13, 21, 34,...#

The ratio of pairs of consecutive terms tends towards the Golden ratio #~~ 1.618034#, which is not too far off #1.609344#.

Hence we find #5# miles is about #8# kilometers, #8# miles is about #13# kilometers, etc.