New to Excel? Looking for a tip? How about a tip so mind-blowingly useful as to qualify as a magic trick? You're in luck. In this Excel tutorial from ExcelIsFun, the 261st installment in their series of digital spreadsheet magic tricks, you'll learn how to generate random numbers within a certain range and with certain supplementary criteria (e.g., values that are not divisible by three) via the use of large array formulas.