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On the Road

Four vehicles travelled on a road. What can you deduce from the times that they met?

There and Back

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?


Age 14 to 16
Challenge Level

  • Why wasn't the second crossing in the same place as the first?

  • If the swimmers can keep this going indefinitely will they have eventually had a crossing point everywhere along the length of the pool?

  • What happens if they both swim twice as fast?

  • What would happen if the pool was twice as long?