At 12 10, Daniel left Town T for Town U, driving at a speed of 63 km/h. At 14 10, Perry also left Town T for Town U driving at a certain speed. Both of them did not change their speed throughout the journey. At 16 10, both of them passed a library that was 189 km away from Town U. How many minutes earlier did Perry reach Town U than Daniel?
Duration that Daniel travelled from 12 10 to 16 10 = 4 h
Distance that Daniel travelled
= 4 x 63
= 252 km
Distance between Town T and Town U
= 252 + 189
= 441 km
Since Perry passed the library at the same time as Daniel, it means that Perry travelled 252 km in 2 hours.
Perry's speed during the journey
= 252 ÷ 2
= 126 km/h
Duration that Perry took to reach Town U after passing the library
= 189 ÷ 126
= 1.5 h
Duration that Daniel took to reach Town U after passing the library
= 189 ÷ 63
= 3 h
Difference between the time they took to reach Town U
= 3 - 1.5
= 1.5 h
1 h = 60 min
1.5 h = 1.5 x 60 = 90 min
Perry reached Town U 90 minutes earlier than Daniel.
Answer(s): 90 min
