Copyright © University of Cambridge. All rights reserved.

## 'Junior Frogs' printed from http://nrich.maths.org/

This challenge is based on the game

Frogs which you may have seen before.

There are two green frogs and two brown toads:

A frog or toad can jump over one other creature onto an empty lilypad or it can slide onto an empty lilypad which is immediately next to it.

Only one creature, at a time, is allowed on each lilypad.

Now the idea is for the frogs and toads to change places. So, the frogs will end up on the side where the toads started and the toads will end up where the frogs began.

The challenge is to do this in as few slides and jumps as possible.

You could use the interactivity below to help you try out your ideas.

To move a frog or toad, click on it. If it is not able to jump or slide, it won't move. The toads and frogs in the interactivity only move in the direction they are facing.

This button

takes you back to the start.

This button

takes you back one step at a time.

This

keeps a record for you - you may also be interested in the grand total of all four parts added together.

Full screen version
This text is usually replaced by the Flash movie.

How do you know you have found the smallest possible number of slides and jumps?

Why not try three frogs and three toads?

What is the smallest number of slides and jumps now?