At 14 10, Perry left Town D for Town E, driving at a speed of 81 km/h. At 16 10, Simon also left Town D for Town E driving at a certain speed. Both of them did not change their speed throughout the journey. At 19 10, both of them passed a library that was 243 km away from Town E. How many minutes earlier did Simon reach Town E than Perry?

Distance that Perry travelled
= 5 x 81
= 405 km

Distance between Town D and Town E
= 405 + 243
= 648 km

Since Simon passed the library at the same time as Perry, it means that Simon travelled 405 km in 3 hours.

Simon's speed during the journey
= 405 ÷ 3
= 135 km/h

Duration that Simon took to reach Town E after passing the library
= 243 ÷ 135
= 1.8 h

Duration that Perry took to reach Town E after passing the library
= 243 ÷ 81
= 3 h

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

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

Simon reached Town E 72 minutes earlier than Perry.

Answer(s): 72 min