**The Banker's Arithmetic**
A teacher, giving an arithmetic lesson, asked: "If someone lends out five yuan with a monthly interest rate of one percent, how much interest will they collect after two years?"
All the students in the class began calculating busily. Only the son of a banker sat still without doing any calculations.
"Why don't you calculate?"
"I'm not interested in such a low interest rate as one percent."
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**Special Purpose**
A salesman sold a computer to a company. A few weeks later, he visited the company again with great confidence but saw that the computer was still sitting there unopened. Surprised, he asked the manager, "Is there something wrong with this computer?"
"Not at all," the manager replied with a smile, "Since we got this computer, our company's efficiency has increased significantly!"
"How is that possible?"
"Every morning, I warn my employees: if you don't work harder and put in more effort, this machine will replace all of you!"