At 14 40, Liam left Town W for Town X, driving at a speed of 60 km/h. At 16 40, Fred also left Town W for Town X driving at a certain speed. Both of them did not change their speed throughout the journey. At 18 40, both of them passed a playground that was 180 km away from Town X. How many minutes earlier did Fred reach Town X than Liam?

Distance that Liam travelled
= 4 x 60
= 240 km

Distance between Town W and Town X
= 240 + 180
= 420 km

Since Fred passed the playground at the same time as Liam, it means that Fred travelled 240 km in 2 hours.

Fred's speed during the journey
= 240 ÷ 2
= 120 km/h

Duration that Fred took to reach Town X after passing the playground
= 180 ÷ 120
= 1.5 h

Duration that Liam took to reach Town X after passing the playground
= 180 ÷ 60
= 3 h

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

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

Fred reached Town X 90 minutes earlier than Liam.

Answer(s): 90 min