7. (6 points) There is a dry well, and the depth of the well is measured using a rope. When the rope is folded in half and lowered to the bottom of the well, one end of the rope is 9 m above the well's mouth; when the rope is folded into thirds and lowered to the bottom of the well, one end of the rope is 2 m above the well's mouth. Then the length of the rope is \qquad meters, and the depth of the well is \qquad meters.
7. (6 points) There is a well without water. To measure the depth of the well, a rope is used. When the rope is folded in half and lowered to the bottom of the well, one end of the rope is 9 m above the well's mouth; when the rope is folded into thirds and lowered to the bottom of the well, one end of the rope is 2 m above the well's mouth. Then the length of the rope is 42 meters, and the depth of the well is $\underline{12}$ meters.
【Solution】Solution: $(9 \times 2-2 \times 3) \div(3-2)$,
$$
\begin{array}{l}
=(18-6) \div 1, \\
=12 \div 1, \\
=12 \text { (meters), } \\
\quad(12+9) \times 2, \\
\text {, } \\
\text { (meters). }
\end{array}
$$
$$
\begin{array}{l}
=21 \times 2, \\
=42 \text { (meters). }
\end{array}
$$

Therefore, the answers are: 42,12.