Four vehicles travelled on a road with constant velocities. The car
overtook the scooter at 12 o'clock, then met the bike at 14.00 and
the motorcycle at 16.00. The motorcycle met the scooter at 17.00
then it overtook the bike at 18.00. At what time did the bike and
the scooter meet?
Brian swims at twice the speed that a river is flowing, downstream
from one moored boat to another and back again, taking 12 minutes
altogether. How long would it have taken him in still water?
At Holborn underground station there is a very long escalator. Two
people are in a hurry and so climb the escalator as it is moving
upwards, thus adding their speed to that of the moving steps. ...
How many steps are there on the escalator?
Two motorboats are travelling up and down a lake at constant
speeds and turning at each end without slowing down. They leave
opposite ends A and B at the same instant, passing each other, for
the first time 600 metres from A and, for the second time, 400
metres from B.
How long is the lake (the distance from A to B) and what is the
ratio of the speeds of the boats?