These two group activities use mathematical reasoning - one is
numerical, one geometric.
What happens if you join every second point on this circle? How
about every third point? Try with different steps and see if you
can predict what will happen.
Arrange the four number cards on the grid, according to the rules,
to make a diagonal, vertical or horizontal line.
We knew a great deal about Tom's number, and
people made good use of the information to figure out what the
number was exactly.
Kevin from Etobicoke, Ontario, Canada
narrowed down the answer by following the clues step by step. Once
he was sure he had Tom's number, he returned to the clues to prove
that his answer was the correct one. Thomas from Tattingstone Primary, near Ipswich, thought
of possible answers and then arrived at his final answer by
eliminating the numbers that would not work for the clues given.
Holly and Joanne, from Moorfield Juniors, used a technique called
guess and check; they chose a number that they estimated was
reasonable and then checked it against each of the
Good detective work led many of you to
finding out what Tom's Number was. Ben, Malcolm and Paul from Yarm
Primary School, Jake and Ben of Moorgate Primary in Tamworth,
Staffordshire, Zoe of Eastbury Farm School, and classmates Matt,
Adam, Dave and Chris all found the answer.
The solutions sounded very much like
entries from Sherlock Holmes. Anis wrote:
From the information that was stated I can conclude that the
Once I knew the number was palindromic I tried dividing 1331,
1221, 1111 and 1001 by 7. 1001 was the only one that gave a whole
number of 143. I divided that by all the odd numbers between 7 and
11. 11 gave me the answer of 13, and as both are prime numbers, I
knew that 1001 was correct.