At 14 55, Lee left Town M for Town N, driving at a speed of 90 km/h. At 16 55, Zeph also left Town M for Town N driving at a certain speed. Both of them did not change their speed throughout the journey. At 19 55, both of them passed a salon that was 180 km away from Town N. How many minutes earlier did Zeph reach Town N than Lee?

Distance that Lee travelled
= 5 x 90
= 450 km

Distance between Town M and Town N
= 450 + 180
= 630 km

Since Zeph passed the salon at the same time as Lee, it means that Zeph travelled 450 km in 3 hours.

Zeph's speed during the journey
= 450 ÷ 3
= 150 km/h

Duration that Zeph took to reach Town N after passing the salon
= 180 ÷ 150
= 1.2 h

Duration that Lee took to reach Town N after passing the salon
= 180 ÷ 90
= 2 h

Difference between the time they took to reach Town N
= 2 - 1.2
= 0.8 h

1 h = 60 min
0.8 h = 0.8 x 60 = 48 min

Zeph reached Town N 48 minutes earlier than Lee.

Answer(s): 48 min