Answer: 12 feet.
Explanation:
1. You know that:
- 29 outlets to be spaced equally over 336 feet.
- There is one at the beginning of the 336 feet and one at the end.
2. Therefore the total number of spaces is:

Where
is the total number of oulets. So you have:

There are 28 spaces.
3. You must divide 336 feet by the number of spaces. Then, you obtain the following result:
