11.3.17 Probability

Question

A pet store has 11 puppies, including 3 poodles, 5 terries, and 3 retrievers. If Rebecka selects one puppy at random. the pet store replaces the puppy with a puppy of the same breed, then Aaron chooses a puppy at random. Find the probability that they both select a poodle.

Answer 1

Hi Kha,

The probability of selecting one of the 3 poodles from the 11 puppies is 3/11.

After the first poodle is replaced, there are again 3 poodles from 11 puppies so the chance of the second also being a poodle is 3/11.

The combined chance of both events happening is 3/11 * 3/11 = 9/121.

Please let me know if I can be more helpful, thanks!

Joe