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Mental Arithmetic (Posted on 2003-10-05)

I can multiply any three-digit number by 1667 in my head, usually in less than 10 seconds.

Also, to make it even more impressive, I come up with the digits of the result in proper order (not in reverse!)

How can I do this?

See The Solution Submitted by nellie

Rating: 3.3333 (6 votes)

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clarification

| Comment 1 of 21

When the author says "...starting with the most significant number", I'm sure she means the most significant digit of the answer.

Posted by Charlie on 2003-10-05 11:22:39

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