These sixteen children are standing in four lines of four, one behind the other. They are each holding a card with a number on it. Can you work out the missing numbers?
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10 will be?
If the numbers 5, 7 and 4 go into this function machine, what numbers will come out?
In sheep talk the only letters used are B and A. A sequence of words is formed by following certain rules. What do you notice when you count the letters in each word?
Square numbers can be represented as the sum of consecutive odd numbers. What is the sum of 1 + 3 + ..... + 149 + 151 + 153?
A mathematician goes into a supermarket and buys four items. Using a calculator she multiplies the cost instead of adding them. How can her answer be the same as the total at the till?
When number pyramids have a sequence on the bottom layer, some interesting patterns emerge...
Esther's detective work and several students' algebraic thinking helped to shed light on Arithmagons.
Go to last month's problems to see more solutions.
Start with any number of counters in any number of piles. 2 players take it in turns to remove any number of counters from a single pile. The winner is the player to take the last counter.