What is the next number in this series?

An old man ordered one hamburger, one order of French fries and one drink. He then unwrapped the burger and carefully cut it in half, placing one half in front of his wife.

He then carefully counted out the French fries, dividing them into two piles and neatly placed one pile in front of his wife.

He took a sip of the drink, and then his wife took a sip and then set the cup down between them.

As he began to eat his few bites of hamburger, the people around them kept looking over and whispering. You could tell they were thinking: "That poor old couple -- all they can afford is one meal for the two of them."

As the man began to eat his fries, a young man came to the table. He politely offered to buy another meal for the old couple. The old man said they were just fine -- they were used to sharing everything.

The surrounding people noticed the little old lady hadn't eaten a bite. She sat there watching her husband eat and occasionally taking turns sipping the drink.

Again the young man came over and begged them to let him buy another meal for them. This time, the old woman said: "No, thank you, we are used to sharing everything."

As the old man finished and was wiping his face neatly with the napkin, the young man again came over to the little old lady, who had yet to eat a single bite of food, and asked: "What is it you are waiting for?"

She answered: "The teeth."