Calculating Bit Strings of Length 7 & 10

[hyderman]

hello

can some one explain this in details thank u

a- How many bit strings of length seven either begin with two 0’s or end with three 1’s?
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b- How many bit strings of length 10 contain either five consecutive 0’s or five consecutive

 

[d_leet]

You need to show some work, but as a hint how many different bit strings are there of arbitrary finite length? How can you modify this to get the number of the strings specified in your post?