Weighing scales

Can you work out how many spheres will balance a single pyramid?
Age
14 to 16
Challenge level
filled star filled star empty star
Exploring and noticing Working systematically Conjecturing and generalising Visualising and representing Reasoning, convincing and proving
Being curious Being resourceful Being resilient Being collaborative

Problem



 

Weighing Scales


Two pyramids and a sphere on one side of a pair of scales will just balance a cube on the other side.

Weighing Scales


A sphere and a cube together will just balance three pyramids.

How many spheres will just balance a single pyramid?

 

If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.