【Question 14】
Given a rectangular piece of paper $A B C D$ with a perimeter of 10 (as shown in the figure), now cut it twice along directions parallel to the length and width, respectively, to form 9 rectangles of unequal sizes. The total perimeter of these 9 rectangles is $\qquad$.


【Analysis and Solution】
Geometry, cleverly finding the perimeter.
Let the length of rectangle $A B C D$ be $a$ and the width be $b$;
then $a+b=10 \div 2=5$;
The total perimeter of these 9 small rectangles = the perimeter of the original rectangle + the segments from the cuts $\times 2$;
The total perimeter of these 9 small rectangles is $10+5 \times 2 \times 2=30$.