You may also like
Times
Which times on a digital clock have a line of symmetry? Which look the same upside-down? You might like to try this investigation and find out!
Clock Hands
This investigation explores using different shapes as the hands of the clock. What things occur as the the hands move.
Ten Green Bottles
Do you know the rhyme about ten green bottles hanging on a wall? If the first bottle fell at ten past five and the others fell down at 5 minute intervals, what time would the last bottle fall down?
Age 7 to 11
Challenge Level
On a digital 24 hour clock, at certain times, all the digits are consecutive (in counting order). You can count forwards or backwards.
For example, 1:23 or 5:43.
How many times like this are there between midnight and 7:00?How many are there between 7:00 and midday?
How many are there between midday and midnight?
Copyright © 1997 - 2023. University of Cambridge.
All rights reserved.
NRICH is part of the family of activities in the Millennium Mathematics Project.
NRICH is part of the family of activities in the Millennium Mathematics Project.