Problem: how many words , with or without meaning , can be formed using all letters of the word good using each letter exactly once ?
Rationale: "the word good has exactly 4 letters which are all different . therefore the number of words that can be formed = number of permutations of 4 letters taken all at a time . = p ( 4 , 4 ) = 4 ! = 4 x 3 x 2 × 1 = 24 answer : e"
annotated_formula: factorial(const_3)