I have no idea what is wrong with my code, when i run this in Xcode it runs fine, but treehouse won't take my answer..

Hey Donghyun Kim,

You're close! The problem is you are misusing String Interpolation. We only use String Interpolation when we can't to extract the value stored inside a variable or constant and place it inside a String literal. A String literal is a representation of an actual string. This is defined as characters between two quotes such as "Hi my name is".

// Enter your code below
let firstValue = 30
let secondValue = 45
let product = firstValue * secondValue
let output = "The product of \(firstValue) times \(secondValue) is \(product)"

You can see I reformatted your code with the correct approach. The value assigned to output will be a single String literal. The parts of the string that do not have their value stored in a backing variable don't need to be interpolated. We can define these sections directly.

Good Luck