Discussion Forum

November 2018 Online ZIML Discussion and Announcements

 
 
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November 2018 Online ZIML Discussion and Announcements
by Areteem Institute - Thursday, November 8, 2018, 9:58 AM
 

Please use this thread for any questions or feedback from the November 2018 Online ZIML Competition.

We hope everyone had fun competing!

 
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Re: November 2018 Online ZIML Discussion and Announcements
by John Lensmire - Thursday, November 8, 2018, 10:14 AM
 

Announcement Regarding Division M Question 7:

Question 7 on the DIvision M Monthly Contest involved a diagram (not drawn to scale) in the shape of a star that included a pentagon in the middle:


The problem stated that $\angle CAD = 20^\circ$ AND that all the outside triangles $\triangle AFJ$, $\triangle BGF$, etc, were all isosceles.

This, however, is impossible, as it both implies that pentagon $FGHIJ$ has interior angles of $100^\circ$ and that it is equiangular (so would have angles of $108^\circ$).

For scoring of the competition, the problem has been removed. The updated problem will state that only $\triangle AFJ$, $\triangle BGF$, and $\triangle CHG$ are isosceles (with $\angle CAD$ still $20^\circ$).