AGE 6-8: Six coins
Julie has six coins.
They are all pound;1 coins, 10p coins or 1p coins.
1. Exactly two of Julie's coins are pound;1 coins.
How much does she have altogether?
There are 5 possibilities. Can you find them?
2. Julie has at least one pound;1 coin, at least one 10p coin, and at least one 1p coin.
How much does Julie have altogether?
There are 10 possibilities. Can you find them?
AGE 9-11: All square
These counters form a square. So do these.
Wat is the greatest number of counters you can put on a 4x4 grid without forming a square?
* ANSWERS page 37 - Brainteaser solutions
On a 2x2 grid you can fit 3 counters,
on a 3x3 grid you can fit 6 counters,
on a 4x4 grid you can fit 10 counters...
without forming a square. For example,
1. The five possibilities are:
pound;2.04, pound;2.13, pound;2.22, pound;2.31, pound;2.40
2. The 10 possibilities are:
pound;4.11, pound;3.21, pound;3.12, pound;2.31, pound;2.22
pound;2.13, pound;1.41, pound;1.32, pound;1.23, pound;1.14