MathDB
Problems
Contests
National and Regional Contests
USA Contests
USA - College-Hosted Events
Stanford Mathematics Tournament
2010 Stanford Mathematics Tournament
13
SMT 2010 General #13
SMT 2010 General #13
Source:
February 11, 2012
number theory
modular arithmetic
Problem Statement
Find all the integers
x
x
x
in
[
20
,
50
]
[20, 50]
[
20
,
50
]
such that
6
x
+
5
≡
19
m
o
d
10
6x+5\equiv 19 \mod 10
6
x
+
5
≡
19
mod
10
, that is,
10
10
10
divides
(
6
x
+
15
)
+
19
(6x+15)+19
(
6
x
+
15
)
+
19
.
Back to Problems
View on AoPS