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Tournament Of Towns
1989 Tournament Of Towns
(227) 1
(227) 1
Part of
1989 Tournament Of Towns
Problems
(1)
TOT 227 1989 Autumn A J1 [ x / 2 ] = [ x / 11 ] +1
Source:
3/12/2021
Find the number of solutions in positive integers of the equation
⌊
x
2
⌋
=
⌊
x
11
⌋
+
1
\lfloor \frac{x}{2} \rfloor = \lfloor \frac{x}{11} \rfloor +1
⌊
2
x
⌋
=
⌊
11
x
⌋
+
1
where
⌊
A
⌋
\lfloor A\rfloor
⌊
A
⌋
denotes the integer part of the number
A
A
A
, e.g.
⌊
2.031
⌋
=
2
\lfloor 2.031\rfloor = 2
⌊
2.031
⌋
=
2
,
⌊
2
⌋
=
2
\lfloor 2\rfloor = 2
⌊
2
⌋
=
2
, etc.
floor function