The figure shown alongside is made from seven small squares. Some of these squares are to be shaded so that:
(i) at least two squares are shaded; (ii) two squares meeting along an edge or at a corner are not both shaded.
How many ways are there to do this?
Select one option, then click Submit.
-1
2
4
5
7
Select an option, then submit.
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Senior Mathematical Challenge 2014 (2014)
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