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Junior Frogs

Age 5 to 11
Challenge Level Yellow starYellow star
  • Problem
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This challenge is based on the game Frogs which you may have seen before. 

There are two blue frogs and two red frogs.

A frog can jump over one other frog onto an empty lilypad or it can slide onto an empty lilypad which is immediately next to it.  
Only one frog, at a time, is allowed on each lilypad.
 
Now the idea is for the blue frogs and red frogs to change places.  So, the red frogs will end up on the side where the blue frogs started and the blue frogs will end up where the red 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.
 



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

Why not try three red frogs and three blue?  
What is the smallest number of slides and jumps now?

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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