I can not pass one test out of five. Kotlin exam. shipping cost calculator

Question

The store uses the following pricing structure:
For US orders:
- orders over $75 have free shipping
- For orders less than $75, shipping costs are 10% of the total order value.

For international orders, shipping charges are 15%, with a maximum of $50. This means that the maximum shipping cost for international orders is $50.

You need to extend this shippingCost() fun, which takes the cost of the order and a boolean indicating whether the order is international and returns the shipping cost for that order.
The return value must be Double.

Code

fun shippingCost(amount: Double, international: Boolean): Double{

var cost: Double

if(international){
if(amount*0.15>=50.0){
cost=50.0
}else{
cost=amount*0.15
}
}else{
if(amount>75.0){
cost=0.0
}else{
cost=75.0*0.1
}
}
return cost

}

fun main(args: Array<String>) {
val total = readLine()!!.toDouble()
val international = readLine()!!.toBoolean()
println(shippingCost(total, international))
}

Answer 1

fun shippingCost(amount: Double, international: Boolean): Double {
var fee : Double = 0.0
if (international) {
fee = 0.15 * amount
if (fee>50) fee=50.0
} else {
if (amount<75) {
fee = 0.10 * amount
}
}
return fee
}

// Good Luck

Answer 2

This line is wrong:
cost=75.0*0.1

Instead, it should be:
cost=amount*0.1

(Why are you always multiplying by 75.0?!)

If you fix the above it works fine!

Let me know if you have any questions