Thanks a lot! I really do not know why i didn´t think of that.
Keep up the good work!

If the value entered is a string it should return "Error".

A float is not a string.

def problem(a):
if isinstance(a,int):
return (a * 50) + 6
else:
return "Error"

This is my code (python)
I get everything right only one error:
"Error" should equal 66
But if my math is good enough I am prett damn sure that 66 would only be posible if a is a float (not a whole number)
where do I have an error?