Copyright © University of Cambridge. All rights reserved.

'Three Frogs' printed from http://nrich.maths.org/

Show menu

3 Funny coloured frogs

Three frogs came in through the kitchen door

Said one to the others "let's explore"

The frogs hopped in and onto the table.

They sat in a line and admired the view - the red frog on the left the green in the middle and the blue frog on the right.

In their excitement they hopped over each other - one frog hopping randomly over any adjacent frog.

After 999 hops they stopped!

Why I do not know - perhaps they were exhausted.

Is it possible, after their 999 hops, for them to have ended up in the position in which they started?