Questions tagged 'Combinatorics'
3 questions
How many subsets of at least one element does a set of six elements have?
What is the total number of subsets that can be formed from a set containing six elements, considering only those subsets that contain at least one element? Answer Choices: A) 64 B) 63 C) 12 D) 42
How many strings of six lowercase letters from the english alphabet contain a) the letter a? b) the letters a and b?
How many strings of six lowercase letters from the English alphabet contain: a) the letter 'a'? b) both the letters 'a' and 'b'?
How many permutations exist of the letters p, q, r, s, and t, taking four at a time?
How many permutations can be formed from the letters p, q, r, s, and t when selecting four letters at a time?