1. **State the problem:** We have a bag with 5 red balls and 3 blue balls. We want to find the probability of picking a blue ball. 2. **Total number of balls:** The total number of balls in the bag is the sum of red and blue balls. $$5 + 3 = 8$$ 3. **Number of favorable outcomes:** The favorable outcomes are picking a blue ball, which is 3. 4. **Calculate the probability:** Probability is the ratio of favorable outcomes to total outcomes. $$\text{Probability} = \frac{\text{Number of blue balls}}{\text{Total number of balls}} = \frac{3}{8}$$ 5. **Final answer:** The probability of picking a blue ball is $$\frac{3}{8}$$.