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iOS Swift Enums and Structs Structs and their Methods Struct Methods

Patrick Glenn
Patrick Glenn
1,363 Points
Posted by Patrick Glenn
Patrick Glenn
1,363 Points

Task 4 of Structs and Methods Challenge

I need to calculate 7.5 percent from the calculateTaxes and then add the result to the variable taxes. I don't understand.

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: "Savings")
item.amount = 100
calulateTaxes(percentage: 7.5)
var taxes = calculateTaxes

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

the task states: 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.

calling a method on an instance of a struct generally looks like this:

structInstanceName.methodName()

in our case the instance is item and the method is calculateTaxes.

you need to call the calculateTaxes method on item and assign the return value to a variable called taxes. the method takes a percentage as an argument. The challenge tells you to use 7.5 percent

struct Expense {
    var description: String
    var amount: Double = 0.0

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

    // add the calculateTaxes method here
    // it should accept only one parameter named 'percentage' of type Double
    func calculateTaxes(percentage: Double) -> Double {
     return self.amount * (percentage/100)

     }

}

var item = Expense(description: "Savings")
item.amount = 100
var taxes = item.calculateTaxes(7.5)
Patrick Glenn
Patrick Glenn
1,363 Points
Patrick Glenn
Patrick Glenn
1,363 Points

Thank you for your help again!