(a) you have 5 1s and 3 0s
so, use the formula for permutations of a set with duplicates:
8!/(5!3!) = 56
That's because for every one of the 8! permutations, the 1s and 0s can be shuffled without altering the string.
(b) and (c) are similar.
Q 8: Count the number of 01-strings with following constraints.
(a) The length is 8. Number of 1s is 2 more than number of 0s.
(b) The length is 8. Number of 1s is 3 more than number of 0s.
(c) The length is 9. Number of 1s is 3 more than number of 0s.
1 answer
1 answer