What is the difference between Accuracy and Precision?

Accuracy & Precision: The story of the cross-bow and the apple

We recently watched a fascinating TED Ed talk by Matt Anticole on YouTube about the difference between accuracy and precision.  Matt uses an analogy of the legend of William Tell, the Swiss folk hero.  

William Tell was an expert marksman with a crossbow who was arrested with his son when he refused to be respectful to the King.  The King said that both he and his son would be executed, but then he King told William Tell he could save his son’s life if he shot through an apple placed on top of his son’s head.  In the legend William Tell is able to shoot the apple and save his son’s life.

The talk considers two alternative scenarios.  Firstly,

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