1. **State the problem:**
We want to find the probability that Rosie does her homework given the probabilities related to her going to the beach and doing homework.
2. **Given probabilities:**
- Probability Rosie goes to the beach: $P(B) = \frac{6}{11}$
- Probability Rosie does homework if she goes to the beach: $P(H|B) = \frac{1}{2}$
- Probability Rosie does homework if she does not go to the beach: $P(H|B^c) = \frac{3}{4}$
- Probability Rosie does not go to the beach: $P(B^c) = 1 - P(B) = 1 - \frac{6}{11} = \frac{5}{11}$
3. **Formula used:**
The total probability that Rosie does her homework is given by the law of total probability:
$$
P(H) = P(H|B)P(B) + P(H|B^c)P(B^c)
$$
4. **Calculate each term:**
$$
P(H|B)P(B) = \frac{1}{2} \times \frac{6}{11} = \frac{6}{22}
$$
$$
P(H|B^c)P(B^c) = \frac{3}{4} \times \frac{5}{11} = \frac{15}{44}
$$
5. **Add the probabilities:**
$$
P(H) = \frac{6}{22} + \frac{15}{44}
$$
To add, find a common denominator:
$$
\frac{6}{22} = \frac{12}{44}
$$
So,
$$
P(H) = \frac{12}{44} + \frac{15}{44} = \frac{27}{44}
$$
6. **Final answer:**
The probability that Rosie does her homework is
$$
\boxed{\frac{27}{44}}
$$
Rosie Homework 57F385
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