Here it is:
While many were left puzzled, the question may appear easier if a simple straight line is drawn downwards dividing X into two equal parts, as shown below:
Now the angle marked is simply the external angle of a regular 12-sided shape. The formula for the external angle of any regular shape is:
where n is the number of sides, i.e. 12.
So
and
It was fairly easy when you know how! But like Hannah's sweets from the English Edexcel board, the trick is spotting how! Expect more of this type of question in years to come, as the exam boards try to separate out pupils who have just learnt the formulas from those who can spot when to use them!
And, of course, social media means we'll get to hear about all of them!
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