The formula with 6.1 substituted
miles = 6.1 ÷ 1.609344 = 3.790
The constant is an exact definition, not a rounded factor: the mile is 1.609344 km, the US gallon is 3.785411784 litres and the imperial gallon is 4.54609 litres. The Kilometres to Miles Converter explains where each comes from and gives a longer table.
At a walking pace of 5 km/h, 6.1 km takes about 73 minutes. At an easy running pace of 10 km/h it takes about 37. In metres it is 6,100.
What 6.1 kilometres means in practice
6.1 km is 3.79 miles and a distance with a famous owner: the full loop of the Central Park drive in New York is 6.1 miles, so runners who search this value have often mixed up the units. As kilometres it is a comfortable 35 minute run.