At 14 40, Vaidev left Town Z for Town A, driving at a speed of 70 km/h. At 16 40, Pierre also left Town Z for Town A driving at a certain speed. Both of them did not change their speed throughout the journey. At 18 40, both of them passed a museum that was 210 km away from Town A. How many minutes earlier did Pierre reach Town A than Vaidev?

Distance that Vaidev travelled
= 4 x 70
= 280 km

Distance between Town Z and Town A
= 280 + 210
= 490 km

Since Pierre passed the museum at the same time as Vaidev, it means that Pierre travelled 280 km in 2 hours.

Pierre's speed during the journey
= 280 ÷ 2
= 140 km/h

Duration that Pierre took to reach Town A after passing the museum
= 210 ÷ 140
= 1.5 h

Duration that Vaidev took to reach Town A after passing the museum
= 210 ÷ 70
= 3 h

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

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

Pierre reached Town A 90 minutes earlier than Vaidev.

Answer(s): 90 min