a speed run is technically Speed work refers to a type of running workout in which you are running for certain intervals near, at, or even faster than your VO2max pace.
42300 / 10 = 4230 4230 * 500 = 2115000 a number multiplied by ten equals to 42300, so 10a = 42300, then a = 4230, then you multiply 4230 and 500 together, which gives you 2115000