A car takes 6 hours to travel from Sokoto to Jos at a constant speed. How long does the same journey take for: a lorry travelling at half the speed of the car?
If the car takes 6 hours to travel from Sokoto to Jos, and the lorry is traveling at half the speed of the car, then the lorry would take twice as long to complete the journey.
Thus, the same journey would take the lorry 6 hours x 2 = <<6*2=12>>12 hours. Answer: \boxed{12}.