Final answer:
The probability of drawing a red marble first and then a green marble is 7/18.
Step-by-step explanation:
The probability of drawing a red marble first and then a green marble can be calculated using the concept of conditional probability. Let's break down the steps:
- Calculate the probability of drawing a red marble first. There are a total of 9 marbles in the bag, so the probability of drawing a red marble first is 4/9.
- Once the first marble is drawn, there will be a total of 8 marbles left in the bag, with 7 of them being green. So, the probability of drawing a green marble after drawing a red marble is 7/8.
- To find the overall probability, multiply the probabilities of drawing a red marble first and then a green marble: (4/9) * (7/8) = 28/72, which simplifies to 7/18.
Therefore, the probability of drawing a red marble first and then a green marble is 7/18.