NRICH: Your Number Is...

Think of a number and follow the machine’s instructions… I know what your number is! Can you explain how I know?

Age 7 to 14

Press the button in the interactivity  and see what happens.

Now try again starting with a different number.

Try again.

Try starting with a fraction… or decimal… or negative number…

Why are your answers ALWAYS the same?

Can you design instructions for similar “Think of a number” machines of your own?
Test them on a partner to check that they lead to your anticipated solutions.
You may want to take a look at Your Number Was… for a suitable follow-up activity.

Math Topics
Algebra & Pre-Algebra, Linear Equations, Quadratic Equations
K-6, Middle School, High School, Educator
2nd Grade, 3rd Grade, 4th Grade, 5th Grade, 6th Grade, 7th Grade, 8th Grade, 9th Grade

What are you looking for?

Organization

NRICH (University of Cambridge)

Website URL

Type of Resource

Online Interactive Activity

Assigned Categories