MathDB
Indonesia Juniors 2014 day 1 OSN SMP

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November 4, 2021
algebrageometrynumber theorycombinatoricsindonesia juniors

Problem Statement

p1. Bahri lives quite close to the clock gadang in the city of Bukit Tinggi West Sumatra. Bahri has an antique clock. On Monday 44th March 20132013 at 10.0010.00 am, Bahri antique clock is two minutes late in comparison with Clock Tower. A day later, the antique clock was four minutes late compared to the Clock Tower. March 66, 20132013 the clock is late six minutes compared to Jam Gadang. The following days Bahri observed that his antique clock exhibited the same pattern of delay. On what day and what date in 20142014 the antique Bahri clock (hand short and long hands) point to the same number as the Clock Tower?
p2. In one season, the Indonesian Football League is participated by 2020 teams football. Each team competes with every other team twice. The result of each match is 33 if you win, 1 1 if you draw, and 00 if you lose. Every week there are 1010 matches involving all teams. The winner of the competition is the team that gets the highest total score. At the end what week is the fastest possible, the winner of the competition on is the season certain?
p3. Look at the following picture. The quadrilateral ABCDABCD is a cyclic. Given that CFCF is perpendicular to AFAF, CECE is perpendicular to BDBD, and CGCG is perpendicular to ABAB. Is the following statements true? Write down your reasons. BDCE=ABCG+ADCF\frac{BD}{CE}=\frac{AB}{CG}+ \frac{AD}{CF} https://cdn.artofproblemsolving.com/attachments/b/0/dbd97b4c72bc4ebd45ed6fa213610d62f29459.png
p4. Suppose M=20142014M=2014^{2014}. If the sum of all the numbers (digits) that make up the number MM equals AA and the sum of all the digits that make up the number AA equals BB, then find the sum of all the numbers that make up BB.
p5. Find all positive integers n<200n < 200 so that n2+(n+1)2n^2 + (n + 1)^2 is square of an integer.