error "function not declared in this scope"

Right now I'm learning arduino denmilanove and our class was assigned to run this exact code below me. The 5 people around me all entered this exact code and got it to work however, when I run it (on 3 different computers) it has given me the same error in the same spot. That being "float SumOfNumbers = FloatAddTwoNumbers(A,B);". Any help would be greatly appreciated.

The point of this code is to do a simple float summation.

void setup()
{
Serial.begin(9600);
float A=1.1;
float B=1.2;
float SumOfNumbers = FloatAddTwoNumbers(A,B);
Serial.print("Sum = ");
Serial.println(SumOfNumbers,DEC);

}

void loop()
{
}

float FloatAddTwoNumbers(float X, float Y);
{
float Sum = X + Y;
return Sum;
}


Error messages:

in function void setup()
floataddtwonumbers is not declared in this scope
at global scope:
error: unexpected unquantified-id before '{' token

You have a stray semicolon here:

float FloatAddTwoNumbers(float X, float Y);

your awesome man thanks! I don't know why the error message kept telling me the error was in the wrong line.

I don’t know why the error message kept telling me the error was in the wrong line.

Since you did not copy the exact error message, you won’t get any answers here.