Using a LinkedHashSet to store random numbers but has duplicates

I have an app that generates a random arithmetic expression. It then generates a correct answer in a random position (tag) and three subsequent incorrect answers allowing the user to choose.

I originally went with an ArrayList but it provides duplicates. I then converted the ArrayList contents in the for loop to a Set and it still produced duplicates. I then changed the initial ArrayList to a LinkedHashSet and alas, still duplicates. i'm thinking it might be the placement in my for loop but I've tried messing around with position and I either encounter duplicates or Index problems.

I don't want to use Java 8's:List<String> deDupStringList3 = strList.stream().distinct().collect(Collectors.toList()); as it's API/Version specific.

For Loop Code:

    List<Integer> answers = new ArrayList<>(new HashSet<Integer>(5));
    answers.clear();

    int incorrectAnswer;

    for (int i = 0; i < 4; i++) {
            if (i == locCorrectAnswer) {
                answers.add(value);
            } else {
                if (operator == '+') {
                    incorrectAnswer = value + rand.nextInt(10) + 1;
                } else {
                    incorrectAnswer = value - rand.nextInt(10) + 1;
                }
                while (incorrectAnswer == value) {
                    if (operator == '+') {
                        incorrectAnswer = value + rand.nextInt(10) + 1;
                    } else {
                        incorrectAnswer = value - rand.nextInt(10) + 1;
                    }
                }
                answers.add(incorrectAnswer);
            }
    }

For Loop code (with ArrayList and conversion to Set):

    ArrayList <Integer> answers;
    Set<Integer> s = new LinkedHashSet<>(answers);

    int incorrectAnswer;

    for (int i = 0; i < 4; i++) {
            if (i == locCorrectAnswer) {
                answers.add(value);
            } else {
                if (operator == '+') {
                    incorrectAnswer = value + rand.nextInt(10) + 1;
                } else {
                    incorrectAnswer = value - rand.nextInt(10) + 1;
                }
                while (incorrectAnswer == value) {
                    if (operator == '+') {
                        incorrectAnswer = value + rand.nextInt(10) + 1;
                    } else {
                        incorrectAnswer = value - rand.nextInt(10) + 1;
                    }
                }
                answers.add(incorrectAnswer);
            }
            s.addAll(answers);
            answers.clear();
            answers.addAll(s);
    }

I'm sure its a simple error but I can't see it.

You can also try the following.

Set<Integer> s = new HashSet<>();
//correct value
s.add(value);
while (s.size() < 4)
{
    //incorrect value
    s.add( value + rand.nextInt(10) + 1);
}
List<Integer> answers = new ArrayList<>(s);
//shuffle
Collections.shuffle(answers);