1. **State the problem:** We have two boxes. The first box contains 4 red and 5 white balls, and the second box contains 6 red and 3 white balls. We pick one ball randomly from each box. We want to find the probability that at least one of the balls picked is red.
2. **Formula and approach:** The probability of "at least one" event happening is easier to find by using the complement rule: $$P(\text{at least one red}) = 1 - P(\text{no red balls})$$
3. **Calculate the probability of no red balls:**
- Probability of picking a white ball from the first box: $$\frac{5}{9}$$ (since total balls = 4 + 5 = 9)
- Probability of picking a white ball from the second box: $$\frac{3}{9} = \frac{1}{3}$$ (since total balls = 6 + 3 = 9)
4. **Calculate the combined probability of no red balls:**
Since the picks are independent, multiply the probabilities:
$$P(\text{no red balls}) = \frac{5}{9} \times \frac{1}{3} = \frac{5}{27}$$
5. **Calculate the probability of at least one red ball:**
$$P(\text{at least one red}) = 1 - \frac{5}{27} = \frac{22}{27}$$
**Final answer:** The probability that at least one ball is red is $$\frac{22}{27}$$.
Probability Red E11Cdf
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