At 10 10, David left Town C for Town D, driving at a speed of 86 km/h. At 12 10, Ryan also left Town C for Town D driving at a certain speed. Both of them did not change their speed throughout the journey. At 14 10, both of them passed a museum that was 258 km away from Town D. How many minutes earlier did Ryan reach Town D than David?

Distance that David travelled
= 4 x 86
= 344 km

Distance between Town C and Town D
= 344 + 258
= 602 km

Since Ryan passed the museum at the same time as David, it means that Ryan travelled 344 km in 2 hours.

Ryan's speed during the journey
= 344 ÷ 2
= 172 km/h

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

Duration that David took to reach Town D after passing the museum
= 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

Ryan reached Town D 90 minutes earlier than David.

Answer(s): 90 min