Find number abc

An engineer, a physicist, and a lawyer were being interviewed for a position as chief executive officer of a large corporation. The engineer was interviewed first, and was asked a long list of questions, ending with "How much is two plus two?" The engineer excused himself, and made a series of measurements and calculations before returning to the board room and announcing, "Four."
The physicist was next interviewed, and was asked the same questions. Again, the last question was, "How much is two plus two?" Before answering the last question, he excused himself, made for the library, and did a great deal of research. After a consultation with the United States Bureau of Standards and many calculations, he also announced, "Four."
The lawyer was interviewed last, and again the final question was, "How much is two plus two?" The lawyer drew all the shades in the room, looked outside to see if anyone was there, checked the telephone for listening devices, and then whispered, "How much do you want it to be?"

A variation

A university committee was selecting a new dean. They had narrowed the candidates down to a mathematician, an economist and a lawyer.
Each was asked this question during their interview: "How much is two plus two?"
The mathematician answered immediately, "Four."
The economist thought for several minutes and finally answered, "Four, plus or minus one."
Finally the lawyer stood up, peered around the room and motioned silently for the committee members to gather close to him. In a hushed, conspiratorial tone, he replied, "How much do you want it to be?"