Twitter 上看到很有趣的方式：
A Mathematician's Way* of Converting Miles to Kilometers
• 1 mi ≈ 1.609 km
• The ratio of consecutive Fibonacci numbers Fₙ₊₁/Fₙ tends to the golden ratio φ ≈ 1.618 as n increases
So Fₙ mi ≈ Fₙ₊₁ km
*This is how I do it ? pic.twitter.com/Jbuwj6rDC1
— Tamás Görbe (@TamasGorbe) August 5, 2019
這邊可以這樣算是因為 1.609 跟黃金比率很接近，而 Fibonacci number 的也有黃金比率的特性，所以可以直接拿來用...