How many hours must you work a day to receive a lunch/break?

Answer:    In NC you're supposed to get a 15 minute break for every four hours you work and at least a 30 minute lunch break for every 8 hours you work.

You have to work at least 6 hours to receive a lunch/dinner break of 30 least in my state. Then for every 4 hours you work, you get a 15 minute break.
4 hours, I believe.

as I am seeing more answers come in - I see that it appears to be a paid 15 minute break for a four hour period of work. That has been true for me in the state of Illinois.
In a day of 8 hours duty, the lunch break will be after 4 hours and a tea has to be served or will be taken within the campus in 2 hours before that. No specifics expect in govt. departments.
That depends upon your state and your age. If you are a minor in the state of Ohio you must receive a 1/2 hour break before you work 5 hours. For adults it is 6 hours or more y ou must be provided the opportunity for a lunch break. I believe there are no laws for 15 minute breaks.
8 hours
4 hours will get you a 10 minute lunch break.
It depends on what state you're in as most labor laws are decided at a state level. I would google it and find the official government web site that addresses it.
Depends on your state and age. Try to google it.
For every 4 hours you work you should get a 15 minute break. You have to work 6 hours for a 30 minute break and I think its 8 hours for an hour break.
Depends on where you live and the employment laws of the state or country you live in.

In the United States, most states require a minimum 30 minute lunch break if you work at least 5 or 6 consecutive hours. Federal law requires you to receive one paid 15 minute break every 4 hours you work (so if you work a normal 8 hour day, you will get two 15 minute breaks). Some states allow you to take only 10 minute breaks if you gain the extra 5 minutes on your lunch (so you would get a 40 minute lunch instead of a 30 minute lunch if you took two 10 minute breaks). Of course, your company could allow you to take an hour lunch (or longer) if that's what the company wants.

As far as other countries, you would have to look up the local laws and figure it out from there.
Where I work at we get (1) 15 minute break and then (1) 30 minute break for lunch. Say if you start at 6 am and then the first break should be about 8.30 am or at 8.45 am. Then in another 2 1/2 to hours or so then we get our lunch break. If we work longer then 8 hours (example: 9 hrs) then we will get another 15 min break. Guess it depends upon the company that you work for.
Depends on where you live. There is no federal US law mandating breaks or lunches. Many states, but not all, do have such laws.

Unless the state has a law with requirements, lunches and breaks are at the option of the employer.
in our company, we are given 15min break for 4hrs work...