Pure Coin-cidence Puzzle - Solution
The Puzzle:

Look at the triangle of six pennies below:
I want to turn this triangle upside-down:

So that it looks like this:

What is the smallest number of coins I must move?
I want to turn this triangle upside-down:

So that it looks like this:

What is the smallest number of coins I must move?
Our Solution:
It is necessary only to move two coins, as the diagrams reveal:


Puzzle Author: Stephen Froggatt
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