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Soros Olympiad in Mathematics
VI Soros Olympiad 1999 - 2000 (Russia)
8.1
p+q+r >= 20 (VI Soros Olympiad 1990-00 R1 8.1)
p+q+r >= 20 (VI Soros Olympiad 1990-00 R1 8.1)
Source:
May 27, 2024
number theory
inequalities
Problem Statement
Let
p
,
q
,
r
p,q,r
p
,
q
,
r
be prime numbers such that
2
p
>
q
2p>q
2
p
>
q
,
q
>
2
r
q > 2r
q
>
2
r
and
q
>
p
+
r
q>p+r
q
>
p
+
r
. Prove that
p
+
q
+
r
≥
20
p+q+r\ge 20
p
+
q
+
r
≥
20
.
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