SOLUTION: How many bit strings of length 4 contain either 3 consecutive 0s or 3 consecutive 1s? Select one: a. 4 b. 7 c. 5 d. 6

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Question 1113018: How many bit strings of length 4 contain either 3 consecutive 0s or 3 consecutive 1s?
Select one:
a. 4
b. 7
c. 5
d. 6
Answer by greenestamps(13203) About Me  (Show Source):
You can put this solution on YOUR website!


What don't you understand about this problem...?

A bit string contains only digits 0 or 1; if a bit string is of length 4, then the total number of different bit strings is 2*2*2*2 = 16. It isn't a lot of work to write out all 16 of those strings and find the ones that have either 3 consecutive 0s or 3 consecutive 1s.

Or you could do just a little basic logical analysis. If a bit string of length 4 has 3 consecutive 0s, what are the possibilities? And likewise if it has 3 consecutive 1s?

And remember that the problem doesn't say EXACTLY 3 consecutive 0s or 1s. The two strings 0000 and 1111 both contain 3 consecutive 0s or 3 consecutive 1s.