At 14 40, Japheth left Town H for Town J, driving at a speed of 79 km/h. At 16 40, Eric also left Town H for Town J driving at a certain speed. Both of them did not change their speed throughout the journey. At 18 40, both of them passed a cinema that was 237 km away from Town J. How many minutes earlier did Eric reach Town J than Japheth?

Distance that Japheth travelled
= 4 x 79
= 316 km

Distance between Town H and Town J
= 316 + 237
= 553 km

Since Eric passed the cinema at the same time as Japheth, it means that Eric travelled 316 km in 2 hours.

Eric's speed during the journey
= 316 ÷ 2
= 158 km/h

Duration that Eric took to reach Town J after passing the cinema
= 237 ÷ 158
= 1.5 h

Duration that Japheth took to reach Town J after passing the cinema
= 237 ÷ 79
= 3 h

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

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

Eric reached Town J 90 minutes earlier than Japheth.

Answer(s): 90 min