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# Cant figure this out

"We need to figure out the tax amount when the tax percentage is 7.5 percent. Call the method calculateTaxes on the variable item and assign the result to a new variable named taxes."

struct.swift
```struct Expense {
var description: String
var amount: Double = 0.0

init (description: String) {
self.description = description
}

func calculateTaxes (percentage: Double) -> Double {
return self.amount * percentage/100
}

}
var item = Expense(description: "Car")
item.amount = 100
```

PLUS

This should do it:

```var taxes = item.calculateTaxes(7.5)
```
##### How does this work?

You created an instance of the `Expenses` struct and assigned it to the variable item before. Now you have access to all methods of this struct via the `item` variable.

```struct Expense {
var description: String
var amount: Double

init (description: String, amount: Double) {
self.description = description
self.amount = amount
}

func calculateTaxes (percentage: Double) -> Double {
return self.amount - (self.amount * (percentage/100))
}

}
var item = Expense(description: "Car", amount: 500)

item.calculateTaxes(7.5)
```

Would you be looking for something like this?