On line 24, if I have 3 equals the conditional statement fails, but with 2 equals it passes. Would love to know why.

function print(message) {
  document.write(message);
}
var questionArray = [
  ['How many states are there?'],
  ['What is the biggest number up to 10?'],
  ['What is better, a cat or dog?']
];

var answerArray = [
  ['50'],
  ['10'],
  ['dog']
];

var quiz = function(questions, answers){
  var correctHTML = '<ol><h1>This is what you got right</h1>';
  var incorrectHTML = '<ol><h1>This is what you got wrong</h1>';
  var guessAnswer;
  for(var i = 0; i < questions.length; i+= 1){
    guessAnswer = prompt(questions[i]);
    if(guessAnswer == answers[i]){
      correctHTML += '<li>' + questions[i] + '</li>';
      correctHTML += '<ul>' + answers[i] + '</ul>';
    } else {
      incorrectHTML += '<li>' + questions[i] + '</li>';
      incorrectHTML += '<ul>The correct answer: ' + answers[i] + '</ul>';
      incorrectHTML += '<ul>What you guessed: ' + guessAnswer + '</ul>';
    }
  }
  correctHTML += '</ol>';
  incorrectHTML += '</ol>';
  print(correctHTML + '<p>' + incorrectHTML + '</>')
};

quiz(questionArray, answerArray);