### The Lily Pond

Freddie Frog visits as many of the leaves as he can on the way to see Sammy Snail but only visits each lily leaf once. Which is the best way for him to go?

### Hypotenuse Lattice Points

The triangle OMN has vertices on the axes with whole number co-ordinates. How many points with whole number coordinates are there on the hypotenuse MN?

### Treasure Island

Write down what you can see at the coordinates of the treasure island map. The words can be used in a special way to find the buried treasure. Can you work out where it is?

# Cops and Robbers

##### Stage: 2, 3 and 4 Challenge Level:

Can you help the police locate the robber?

The robber is hiding in a modern city, where the roads are all at right angles and equally spaced. Imagine the grid lines represent roads. The robber is hiding at a crossroads.

Input coordinates to help the police search and find the robber with the fewest guesses. The interactivity gives you the shortest distance you'd have to travel (along the roads) to reach the robber.

Can you find a reliable strategy for choosing coordinates that will locate the robber in the minimum number of guesses?

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