Solution: The bus runs more than the truck every hour: 27/4.5 = 6 km/h.
AB the distance between the two places:
6/(5-4)*(5+4)*4.5
=54*4.5
= 243 km
(2) Two ships leave from Port A and Port B relatively simultaneously. The speed of passenger ships is 42 kilometers per hour, and the speed of cargo ships is 5/6 of that of passenger ships. Two ships meet at the midpoint of port A and port B 7 kilometers. What is the distance between port A and port B?
Solution: cargo speed: 42 * 5/6 = 35 km/h.
The distance between port a and port b is:
7*2/(42-35)*(42+35)
=2*77
= 154km。