I don't know what test to use to see if there is a relationship between two sets of data when they rely on each other.

Example:

# of people who slipped on wet floor: day 1 - 7. Day 2 - 8. Day 3 - 7.

# of people who slipped on dry floor: day 1 - 3. Day 2 - 2. Day 3 - 3. . .

Basically the number of people is always 10. I don't think I can do a chi square test because if one number changes, then so does the other. Is there a specific test for this situation?