At 11 45, Luis left Town Y for Town Z, driving at a speed of 99 km/h. At 13 45, Oliver also left Town Y for Town Z driving at a certain speed. Both of them did not change their speed throughout the journey. At 16 45, both of them passed a school that was 297 km away from Town Z. How many minutes earlier did Oliver reach Town Z than Luis?

Distance that Luis travelled
= 5 x 99
= 495 km

Distance between Town Y and Town Z
= 495 + 297
= 792 km

Since Oliver passed the school at the same time as Luis, it means that Oliver travelled 495 km in 3 hours.

Oliver's speed during the journey
= 495 ÷ 3
= 165 km/h

Duration that Oliver took to reach Town Z after passing the school
= 297 ÷ 165
= 1.8 h

Duration that Luis took to reach Town Z after passing the school
= 297 ÷ 99
= 3 h

Difference between the time they took to reach Town Z
= 3 - 1.8
= 1.2 h

1 h = 60 min
1.2 h = 1.2 x 60 = 72 min

Oliver reached Town Z 72 minutes earlier than Luis.

Answer(s): 72 min