Do while loop that calculates average while not accounting for negative numbers?

Question

Need to write a javascript code that will prompt a user to enter numbers until a negative number is entered. Then calculate the average of the positive numbers only. Any help is much appreciated.

Here is what I have so far:

do{
  if(num < 0){
    alert("You entered a negative number");
    break;
  }else if(num >= 0){
    num = +prompt("enter another number");
    sum += num;
    count++;
  }
}while(num != -1){
    console.log(sum/count);
}

Answer 1

Check this

var sum=0;
var count=0;
do{
    var num = prompt("enter another number");
  if(num < 0){
    alert("You entered a negative number");
    break;
  }else {
    sum += parseInt(num,10);
    count++;
  }
}while(true);

alert(sum/count);

Answer 2

do{
  if(num < 0){
    alert("You entered a negative number");
    break;
  }else if(num >= 0){
    num = prompt("enter another number");
    sum += num;
    count++;
  }
}while(num > 0)

    console.log(sum/count);