### Pair Sums

Five numbers added together in pairs produce: 0, 2, 4, 4, 6, 8, 9, 11, 13, 15 What are the five numbers?

### Summing Consecutive Numbers

Many numbers can be expressed as the sum of two or more consecutive integers. For example, 15=7+8 and 10=1+2+3+4. Can you say which numbers can be expressed in this way?

### Big Powers

Three people chose this as a favourite problem. It is the sort of problem that needs thinking time - but once the connection is made it gives access to many similar ideas.

# Creating Squares - Game

##### Age 11 to 16

This resource is part of "Dotty Grids - Drawing Polygons"

In this game, two players take it in turns to click on a dot on the grid.
The winner is the first to have four vertices of a square in their colour.

Play a few games against the computer or a friend.

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Can you develop any winning strategies?
Can you suggest any mathematically interesting variations on the game?