Question
A binary string of length $n$ is a string of $n$ characters that are each $0$ or $1$. Find the number of binary strings of length $n$ that either begin with $1$ or end with $00$. Report the answer for $n = 10$.
easy Probability
Binary Strings
A release-checked easy problem for training Inclusion-Exclusion, Combinations and Permutations.
Practice focus
This Probability problem is tagged Inclusion-Exclusion, Combinations and Permutations. State the random variables and conditioning information explicitly, then check the result against boundary cases before opening hints or a solution.
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