You may also like

problem icon

Building Tetrahedra

Can you make a tetrahedron whose faces all have the same perimeter?

problem icon

Ladder and Cube

A 1 metre cube has one face on the ground and one face against a wall. A 4 metre ladder leans against the wall and just touches the cube. How high is the top of the ladder above the ground?

problem icon

Areas and Ratios

What is the area of the quadrilateral APOQ? Working on the building blocks will give you some insights that may help you to work it out.

Fibonacci Deduction

Stage: 4 Short Challenge Level: Challenge Level:1

If we let the fifth number be $x$, then the sixth number is $6+x= 15$, so $x=9$.
The seventh number is the sum of the fifth and sixth numbers, $9+15=24$.

This problem is taken from the UKMT Mathematical Challenges.