Bill Rancic (left) won Donald Trump's first series

The first two series have seen men compete against women for a high-earning role in his business empire.

They have to complete tasks, with one being "fired" each episode.

For the third series, high-school graduates will compete against entrepreneurs whose education finished when they left school.

"We wanted to see what would happen if we pitted college grads - book smarts - against high school grads - street smarts," Mr Trump said in a statement.

Mr Trump graduated from the University of Pennsylvania's Wharton School of business, before starting work in his father's property business.

Ratings for The Apprentice's second season were lower than for its debut in the spring.

But it was the second most-watched reality TV show behind desert island castaway series Survivor, and it came 12th in the ratings for all prime-time programmes.