MathDB
Problems
Contests
National and Regional Contests
Peru Contests
Peru Cono Sur TST
2020 Peru Cono Sur TST.
P8
P8
Part of
2020 Peru Cono Sur TST.
Problems
(1)
minimize adjacent products
Source: Peru Cono Sur TST 2020 P7
9/11/2023
Let
n
≥
2
n \ge 2
n
≥
2
. Ana and Beto play the following game: Ana chooses
2
n
2n
2
n
non-negative real numbers
x
1
,
x
2
,
…
,
x
2
n
x_1, x_2,\ldots , x_{2n}
x
1
,
x
2
,
…
,
x
2
n
(not necessarily different) whose total sum is
1
1
1
, and shows them to Beto. Then Beto arranges these numbers in a circle in the way she sees fit, calculates the product of each pair of adjacent numbers, and writes the maximum value of these products. Ana wants to maximize the number written by Beto, while Beto wants to minimize it. What number will be written if both play optimally?
combinatorics
games