Question 21
Andy’s house password is a three-digit sequence. He forgot it and made the four attempts shown. Find the password using these clues.
1st attempt: One digit is correct and in the right place.
2nd attempt: One digit is correct but in the wrong place.
3rd attempt: Two digits are correct, both in the wrong places.
4th attempt: All digits are incorrect.
Grading clarification: as in the supplied solution, “one” and “two” mean exactly those numbers of correct digits.
1st attempt: One digit is correct and in the right place.
2nd attempt: One digit is correct but in the wrong place.
3rd attempt: Two digits are correct, both in the wrong places.
4th attempt: All digits are incorrect.
Grading clarification: as in the supplied solution, “one” and “two” mean exactly those numbers of correct digits.