"Back In The Old Days" joke
Back in the old days - when slide rules were still the most sophisticated computing equipment available to scientists and engineers...
Engineering students are taking a math final. Of course, slide rules are not allowed. And, of course, someone is cheating and has brought a slide rule to the exam. He is hiding it under his desk, but the student sitting to his left - who is stuck on a difficult calculation - has noticed it.
"Hey", he whispers. "Can you help me? What's three times six?"
His classmate reaches for his slide rule, and after a few seconds replies: "Nineteen."
"Are you sure?"
The other student reaches again for his slide rule, and after another few seconds replies: "You're right. It's closer to eighteen - eighteen point three, to be precise."
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