"Improbability Drive," she said patiently. "You explained it to me yourself. We pass through every point in the Universe, you know that."
"Yeah, but that's one wild coincidence isn't it?"
"Yes."
"Picking someone up at that point? Out of the whole of the Universe to choose from? That's just too ... I want to work this out. Computer!"
The Sirius Cybernetics Corporation Shipboard Computer which controlled and permeated every particle of the ship switched into communication mode.
"Hi there!" it said brightly and simultaneously spewed out a tiny ribbon of ticker tape just for the record. The ticker tape said, Hi there!
"Oh God," said Zaphod. He hadn't worked with this computer for long but had already learned to loathe it.
The computer continued, brash and cheery as if it was selling detergent.
"I want you to know that whatever your problem, I am here to help you solve it." "Yeah yeah," said Zaphod. "Look, I think I'll just use a piece of paper."
"Sure thing," said the computer, spilling out its message into a waste bin at the same time, "I understand. If you ever want ..."
"Shut up!" said Zaphod, and snatching up a pencil sat down next to Trillian at the console.
"OK, OK ..." said the computer in a hurt tone of voice and closed down its speech channel again.
Zaphod and Trillian pored over the figures that the Improbability flight path scanner flashed silently up in front of them.
"Can we work out," said Zaphod, "from their point of view what the Improbability of their rescue was?"
"Yes, that's a constant", said Trillian, "two to the power of two hundred and seventy-six thousand seven hundred and nine to one against."
"That's high. They're two lucky lucky guys."
"Yes."