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BEBRAS 2021 Grade 5-6 Round 2 Ext Question 8

BEBRAS · BEBRAS 2021 Grade 5-6 Round 2 Ext

Question 8

A beaver engineer makes triangular windows by this procedure.
1. Make an equilateral triangular frame.
2. Join the midpoints of its sides to create four triangles.
3. Put gray glass in the central triangle.
4. Repeat steps 2 and 3 in any one pane that has not yet received glass.
Step 4 may be repeated any number of times. How many of these six windows can be made?

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