OBF Third Phase Problems

2025

Brazil

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

2024

Brazil

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

2020

Brazil

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

2017

Brazil

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

2016

Brazil

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

2015

Brazil

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

2014

Brazil

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

2011

Brazil

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

2010

Brazil

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

2009

Brazil

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

2007

Brazil

Problem 1

Problem Solution

Problem 2

Problem Solution

Problem 3

Problem Solution

Problem 4

Problem Solution

Problem 5

Problem Solution

Problem 6

Problem Solution

Problem 7

Problem Solution

Problem 8

Problem Solution

2006

Brazil

Problem 1

Problem Solution

Problem 2

Problem Solution

Problem 3

Problem Solution

Problem 4

Problem Solution

Problem 5

Problem Solution

Problem 6

Problem Solution

Problem 7

Problem Solution

Problem 8

Problem Solution