"The answer was: very." What is the effect of this short sentence?

Rohan had checked the platform number three times. He had checked the train number twice. He had even asked a porter. So when the ticket collector looked at his ticket and said, "This is for the Karnataka Express, sir. This is the Kerala Express," Rohan did not believe him.

"But they left from the same platform," he said.

"Twenty minutes apart," said the ticket collector kindly. "It happens more than you would think."

The next station was three hours away. Rohan sat down heavily on his bag in the doorway and began to calculate how late he would be for his cousin's wedding. The answer was: very.

The old woman in the seat beside the door, who had been watching the whole thing over her glasses, patted the space next to her. "Sit," she said. "You look like you need tea."

It turned out she had been making the same journey every month for thirty years to see her daughter. She knew which stations had the best vadas, which chaiwala added cardamom, and exactly where Rohan should get off to catch a bus back the way he had come.

He reached the wedding four hours late, just in time for the dinner. His cousin laughed at him for weeks.

But when Rohan told the story afterwards, it was never about the wedding. It was about the woman who had given him her vadas, her tea and her timetable, and had refused, absolutely, to let him pay.