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
This investigation explores using different shapes as the hands of
the clock. What things occur as the the hands move.
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?
Julian of Hethersett High School made a table
of the days of the week on 1 January every year from the year 2000
to the year 2100. He used the fact that the day of the week 'moves
on' by $1$ day each year (why is that?) apart from immediately
after a leap year when it 'moves on' by $2$ days. The pattern
repeats after $28$ years.
The first Saturday 1 st January after 2060 is in 2061
so Millennium Man will retire on his 61 st birthday. The
1st January falls on a Saturday four times every $28$
years. It falls on a Saturday $15$ times this century so his
birthday will occur on a Saturday $15$ times during this
Well done also Lizzie and Hollie, The Mount
School, York and Fiona, Stamford High School, Lincolnshire.
Congratulations also to Katherine and Rosalind from Chawson First
School Droitwich who told us:
We made a note of which years were leap years
and then counted up all the Saturdays. The first question came out
as 2061 and the second came out as $15$.