A princess is as old as the princ will be when the princess is twice as old as the prince was when the princess' age was half of the sum of their present age.
Which of the following, then, could be true?
1. The prince is 20 and the princess 30.
2. The prince is 40 and the princess 30.
3. The prince is 30 and the princess 40.
4. The prince is 30 and the princess 20.
5. They are both the same age.