Answer:
bag 3
Step-by-step explanation:
Let's call the labels "green", "red", and "mix".
Pick mix for two reasons :
- First, it's not mixed so whatever color you pick is the color of the pair.
- Also, if you pick from either of the other two, you can't know if it's a mixed bag or not.
So, let's pretend you pick a red out. Move the label red to the bag. This must be true - cannot be a mix.
Now, you have the mix label <u>in your hand</u>, <u>one bag with a label</u> (green), and <u>one bag without a label</u> (previously red).
Since all bags mislabeled to begin, move the green label to the <u>blank bag</u> - since this label must be wrong.
Put the mix label on the <u>remaining bag</u>.