• Since Mary and Tina live in the same color houses, they both live in the green houses (1 and 6).

• Since Tina was the last person to see your friend, she lives in the middle or last house on her street.
• Thus, Tina lives in house 6, and Mary lives in house 1. That means your missing friend lives in house 4.

• Two girls live on the even side of the street. We know Mary lives in house 1, so both Tina and Rosa must live on the even side of the street.

• Either Walt or Ryan lives on the even side of the street, so we know that the other one of them lives on the even side of the street, along with Tina and Rosa.

Rosa is alphabetically before Tina, Walt, and Ryan, so she must be your missing friend.

You can deduce the following information from the logic clues:

-Since Tina was the last person to see your friend, she lives in the middle or last house on the street.

-Since Mary and Tina live in the same color houses, they both live in the green houses (1 and 6).

-Thus, Tina lives in house 6, and Mary lives in house 1. That means your missing friend lives in house 4.

-Two girls live on the even side of the street. We know Mary lives in house 1, so both Tina and Rosa must live on the even side of the street.

-Also either Walt or Ryan lives on the even side of the street, so we know that Tina, Rosa, and Walt or Ryan lives on the same street.

-Rosa is alphabetically before Tina, Walt, and Ryan, so she must be your missing friend.

The lock opens with the word Rosa.