Answer by
esteban (1334)
There are 1. 609344 kilometers in one mile. Therefore, if you know the speed in miles per hour, just multiply it by 1. 609344. This will give you a value that is probably more accurate than you need, so you will need to round. Here's an example: 25 miles per hour is 40. 2336 kilometers per hour because 25 X 1. 609344 = 40. 2336.