Indonesia Juniors 2014 day 2 OSN SMP
Source:
November 4, 2021
algebrageometrynumber theorycombinatoricsindonesia juniors
Problem Statement
p1. Nurbaya's rectangular courtyard will be covered by a number of paving blocks in the form of a regular hexagon or its pieces like the picture below. The length of the side of the hexagon is cm.
https://cdn.artofproblemsolving.com/attachments/6/1/281345c8ee5b1e80167cc21ad39b825c1d8f7b.png
Installation of other paving blocks or pieces thereof so that all fully covered page surface. To cover the entire surface
The courtyard of the house required paving blocks. How many paving blocks must be cut into models , and for the purposes of closing. If pieces of model paving blocks are needed, how many the length and width of Nurbaya's yard? Count how much how many pieces of each model , and paving blocks are used.
p2. Given the square . If one side lies on the line and its two vertices lie on the parabola , find the maximum area of possible squares .
p3. In the triangular pyramid , the points , and lie at , respectively , , , and so that . Determine the ratio of the volumes of the two halves of the divided triangular pyramid by the plane .
p4. We know that is a non-negative integer and is an integer. Define all pair that satisfy .
p5. The coach of the Indonesian basketball national team will select the players for become a member of the core team. The coach will judge five players and in one simulation (or trial) match with total time minute match. At any time there is only one in five players that is playing. There is no limit to the number of substitutions during the match. Total playing time for each player , and are multiples of minutes, while the total playing time of each players and are multiples of minutes. How many ways each player on the field based on total playing time?