A bag contains 4 red balls and 6 blue balls. If a ball is drawn at random from the bag, what is the conditional probability that the ball drawn is red given that it is not blue?

Step 1 ：Step 1: Identify the total number of outcomes. In this case, there are 10 balls in total, so the total number of outcomes is 10.

Step 2 ：Step 2: Identify the number of outcomes that meet the condition. Since we are given that the ball is not blue, we only consider the red balls. There are 4 red balls.

Step 3 ：Step 3: The conditional probability is given by the formula \( P(A|B) = \frac{P(A \cap B)}{P(B)} \). In this case, since red and blue are mutually exclusive events (a ball cannot be both red and blue), \( P(A \cap B) = P(A) \), which is the probability of drawing a red ball.

Step 4 ：Step 4: Calculate the probabilities. \( P(A|B) = \frac{P(A)}{P(B)} = \frac{4}{10} = 0.4 \)