.
A car driver and a truck driver started from the same place and headed
for the same destination 480km away. The car set off 90min later than the truck
but arrived 90min earlier. If the average speed of the truck was 60km per hour,
what was the average speed of the car.
~~~~~~~~~~~~~~~~
The truck traveled = 8 hours.
For the car, the travel time was 90+90 = 180 minutes = 3 hours LESS than 8 hours.
Hence, for the car, the travel time was 8-3 = 5 hours.
It means that the car's average rate was = 96 kilometers per hour.
Solved.
--------------------
Today's morning tasks are much more reasonable than the usual ones at this time of a day.
The impression is as if the sun of reason shone in the east.