### Two Numbers Under the Microscope

This investigates one particular property of number by looking closely at an example of adding two odd numbers together.

### Odd Times Even

This problem looks at how one example of your choice can show something about the general structure of multiplication.

### Walking Round a Triangle

This ladybird is taking a walk round a triangle. Can you see how much he has turned when he gets back to where he started?

# A Bag of Marbles

##### Age 5 to 7Challenge Level

Suppose that in a bag of marbles, all the ones that -

are rough to feel, have a blue colour on them;

sparkle when rolling, have a red colour on them;

are cold to touch, have a white colour on them;

are dark inside, have a green colour on them.

What can you say about each of the marbles A - J?

Imagine you are making marbles. What colours must be put on marbles that -

sparkle when rolling but are dark inside?

are cold to touch and feel rough?

are cold, but sparkle when rolling?

What colour(s) could be on a marble that -

is cold?

sparkles when rolling?

What colours would you find on a cold, sparkly, dark and rough marble?