Treadmill: 10 km

I usually go to the gym 3-4 times a week and I do the bodybuilding routine. Before and after workout I jog 3 km. Once a week I have cardio. In most cases it is treadmill. Now I can easily run 7 km. I believe I can run 10 km under 90 minutes. My plan is to increase the distance every week by 1 km. One month is enough to achieve this goal!