BRAIN TRIVIA
Solution:
1639 or 1934
Explanation:
Code breakers: find the correct 4-digit combination using the numbers 1-9, with no repeats. (Hint: there are 2 potential solutions)
1 8 5 7 - 1 digit is correct and in the correct position
2 6 3 4 - 2 digits are correct and in the correct positions
9 2 1 3 - 3 digits are correct but all in the wrong positions
5 8 7 2 - None of the digits are correct
From clue 4, you can remove those numbers from all of the other clues. This leaves us with:
1
857- 1 digit is correct and in the correct position26 3 4 - 2 digits are correct and in the correct positions9
21 3 - 3 digits are correct but all in the wrong positions5872- None of the digits are correct
From clue 1, this means the first digit is 1.
From clue 3, this means two of the remaining three numbers are 9 and 3.
From clue 2, this means that the remaining number is either 6 or 4 (so either 6 and 3 are correct and in the correct positions, or 3 and 4 are correct and in the correct positions).
If the numbers 6 and 3 in clue 2 are correct, then the answer is: 1 6 3 9
If the numbers 3 and 4 in clue 2 are correct, then the answer is: 1 9 3 4