Solution of the Week #341 - Mastermind

From guess 3, one is in the correct place. It cannot be the initial Red as that would have shown as in the correct place in guess 1. Similarly it cannot be the final purple, as guess 2 would have shown it. So it must be the red in position 2.

Since the first two guesses cover all of the colours, but only show two correct pegs, there must be a colour repeated. It cannot be the red, or else that would have shown in guess 3. It must be one of the colours from guess 2, but since they must occupy positions 1 and 3 in the answer, they cannot be Orange or Purple, as they would have shown as in the correct place in guess 2.

The final answer is therefore Blue Red Blue