At 11 40, Ivan left Town S for Town T, driving at a speed of 87 km/h. At 12 40, Elijah also left Town S for Town T driving at a certain speed. Both of them did not change their speed throughout the journey. At 15 40, both of them passed a playground that was 174 km away from Town T. How many minutes earlier did Elijah reach Town T than Ivan?

Distance that Ivan travelled
= 4 x 87
= 348 km

Distance between Town S and Town T
= 348 + 174
= 522 km

Since Elijah passed the playground at the same time as Ivan, it means that Elijah travelled 348 km in 3 hours.

Elijah's speed during the journey
= 348 ÷ 3
= 116 km/h

Duration that Elijah took to reach Town T after passing the playground
= 174 ÷ 116
= 1.5 h

Duration that Ivan took to reach Town T after passing the playground
= 174 ÷ 87
= 2 h

Difference between the time they took to reach Town T
= 2 - 1.5
= 0.5 h

1 h = 60 min
0.5 h = 0.5 x 60 = 30 min

Elijah reached Town T 30 minutes earlier than Ivan.

Answer(s): 30 min