The FitnessGram PACER Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The test is used to measure a student's aerobic capacity as part of the FitnessGram assessment. Students run back and forth as many times as they can, each lap signaled by a beep sound.

When visiting his parents, tyler drives at an average speed of 42 km/h through urban areas, and at an average speed of 105 km/h along the motorway. his journey usually takes him 2.5 hours. one day when there is a fog, he sets off 1 hour early and only manages to average 28 km/h in urban areas and 60 km/h on the motorway. he arrives 30 minutes late. how long was tyler journey?