We will be working under the assumption that all three riders sat on one horse at a time and rode it while the other horses rested.
From the problem, we can understand that the horses were each ridden for the same distance. This means that to get the total distance a horse rode before it was changed, we can divide the total distance by the number of horses that were used for the journey.
Distance each horse rode = 182/ 13 = 14 miles.
Therefore, each horse was ridden for 14 miles before it was changed.
