I'm trying to write a program to check if a number is a power of 5, but I came across a weird problem. Bellow is a code which illustrates my issue: 
my $x = 125;
my $l = log($x) / log(5);

print "LOG      == $l\n";
print "int(LOG) == ", int($l), "\n";

print "Are equal: ", ($l == int($l)) ? "true\n" : "false\n";

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It prints: 
LOG      == 3
int(LOG) == 3
Are equal: false

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For $x = 25 it works as expected, but for  $x = 125 (and probably other numbers), it acts really weird. It says that 3 != int(3). I'm wondering how is this possible... Is there some explanation for this?

Thank you

In reply to log() and int() problem by Anonymous Monk

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