3

Part of 2013 May Olympiad

Problems(2)

May Olympiad 2013, Level 2, Problem 3

Source:

Many distinct points are marked in the plane. A student draws all the segments determined by those points, and then draws a line r that does not pass through any of the marked points, but cuts exactly

60

drawn segments. How many segments were not cut by r? Give all possibilites.

square paper folding (May Olympiad 2013 L1)

Source:

ABCD

be a square of side paper

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P

a point on side

BC

. By folding the paper along the

AP

B

determines the point

Q

, as seen in the figure. The line

PQ

CD

R

. Calculate the perimeter of the triangle

PCR

https://3.bp.blogspot.com/-ZSyCUznwutE/XNY7cz7reQI/AAAAAAAAKLc/XqgQnjm8DQYq6Q7fmCAKJwKt3ihoL8AuQCK4BGAYYCw/s400/may%2B2013%2Bl1.png

geometrysquarepaperperimeter