Answer:
Step-by-step explanation:
When the first draw is done there are 9 red balls in a sample size of 21. So there probability of drawing a red ball will be
When the second draw is done, there will be 12 yellow balls in a sample size of 20 since the first ball will not have been replaced into the bag. So the chance of someone drawing the second ball in the second draw is
The probability of them happening in this order is the product of both probabilities: