There are exactly 14 possible numbersthat if you multiply them by 7 you'll get a 4 digit number that is 3--7 (that is: 3 in the thousands and 7 in the ones): 441, 451, 461, 471, 481, 491, 501, 511, 521, 531, 541, 551, 561, 571 Please note that the number must end with 1 cause the only way to get ...