Puzzle of the Week #496 - Four Towns

I wish to travel to Torton which is generally in the north-east direction of where I’m starting in Kipton.

If I go directly from Kipton to Torton it takes me 78 minutes.

Lawton is a town 15 miles due east of Kipton.

If I go from Kipton to Lawton and then on to Torton it takes me 102 minutes.

Gunton is a town 16 miles due north of Kipton.

If I go from Kipton to Gunton then on to Torton it takes me 82 minutes.

You can assume there are straight roads between each of the towns and I always travel at a constant rate.

How far is it from Kipton to Torton?