Measuring with Rods

A fence made out of giant pencils
You can use rods of lengths 3, 4 and 6 units to measure different lengths.

The diagrams shows how to measure lengths of 1, 3, 5 and 7. 

Can you see how to measure a length of 2?

There are rods for 4 and 6, so it's possible to measure all the lengths from 1 to 7.

Can you convince yourself you cannot measure a length of 8?


Can you find another set of three rods that can be used to measure all the lengths from 1 to 7?

What about 1 to 8?

1 to 9?

1 to ...?


How far can you go? Take a look at Longer and Longer to explore further.