Answer: The answer is 84 inches.
Step-by-step explanation: It is given that twelve round gold medals fit inside a box where 4 medals are placed in one ray. So, the number of rows in the box is 3.
The radius of each gold medal = 3 inches.
Therefore, diameter of each gold medal = 2 × 3 = 6 inches.
The box is obviously in the rectangular form where

The red tape fits snugly around the sides of the box, so it will cover whole of the box.
Therefore, the length of the tape = 24+18+24+18 = 84 inches.