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How many 5-digit numbers (it...

How many 5-digit numbers (it cannot start with 0) are there that do not contain the numbers 3 and 5, and are multiples of 4?

Correct answers: 23

The first user who solved this task is Manguexa Wagle.

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Hot Horseradish

A minister who was very fond of pure, hot horseradish always kept a bottle of it on his dining room table. Once, at dinner, he offered some to a guest, who took a big spoonful.The guest let out a huge gasp. When he was finally able to speak, he choked out, "I've heard many ministers preach hellfire, but you are the first one I've met who passes out a sample of it."

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Screw-blank feeder mechanism

In 1856, Cullen Whipple, of Providence, RI, patented a screw-blank feeder mechanism (U.S. No. 15,052). In Oct 1840, he was one of ten incorporators of The New England Screw Co. He invented a machine for the company to use cutting the threads of screws (patented 18 Aug 1842) which he later improved by adding more cutters to also point the screws in the same machine (patent No. 9,477, 14 Dec 1852). He patented various other devices for improving the manufacture of screws. He has been credited* as the inventor of the first practical machine for pointing screws. Early screws had no point and required that a starter hole be drilled before use.«[Note: Famous First Facts by Joseph Nathan Kane incorrectly cites this screw-blank feeder mechanism's 3 Jun 1856 date and patent number as the first practical screw-pointing machine patent. In fact, Whipple invented his screw pointing machine four years earlier - in 1852.]

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