Calculate the number 787
NUMBERMANIA: Calculate the number 787 using numbers [4, 7, 4, 7, 10, 764] and basic arithmetic operations (+, -, *, /). Each of the numbers can be used only once.Correct answers: 3
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First printing press invented in the U.S.In 1816, the Columbian Press, the first printing press invented in America, was designed by George E. Clymer in Philadelphia, Pa. It was an iron horizontal platen hand-printing press using a system of compound levers that multiplied the pull of the operator to replace the iron screw previously used for downward pressure. An eagle-shaped counterweight lifted the platen back after the pressman's "pull". The Columbian was somewhat well-received in America, even at $400, which was twice the cost of a wooden press. In 1818, Clymer took his business to England and found much greater success. He joined forces with William Dixon in 1825. From the 1840s, the presses were manufactured by companies all over Europe. |