At 14 50, Mark left Town C for Town D, driving at a speed of 86 km/h. At 17 50, Tim also left Town C for Town D driving at a certain speed. Both of them did not change their speed throughout the journey. At 20 50, both of them passed a cafe that was 258 km away from Town D. How many minutes earlier did Tim reach Town D than Mark?

Distance that Mark travelled
= 6 x 86
= 516 km

Distance between Town C and Town D
= 516 + 258
= 774 km

Since Tim passed the cafe at the same time as Mark, it means that Tim travelled 516 km in 3 hours.

Tim's speed during the journey
= 516 ÷ 3
= 172 km/h

Duration that Tim took to reach Town D after passing the cafe
= 258 ÷ 172
= 1.5 h

Duration that Mark took to reach Town D after passing the cafe
= 258 ÷ 86
= 3 h

Difference between the time they took to reach Town D
= 3 - 1.5
= 1.5 h

1 h = 60 min
1.5 h = 1.5 x 60 = 90 min

Tim reached Town D 90 minutes earlier than Mark.

Answer(s): 90 min