Question

1. Find the probability of this set of independent events. rolling a six on the first roll of a 1-6 number cube and rolling an odd number on the second roll of the same cube
2. Find the probability of this set of independent events.
drawing a 1, 2, or 3 from 9 cards numbered 1-9, replacing the card, and drawing a 7, 8, or 9
3. A bag contains 3 blue marbles and 2 green marbles. What is the probability of drawing a blue marble followed by a green marble, without replacing the first marble before drawing the second marble?

Answer 1

For the first question, the chance of rolling a six is a 1/6 chance because there is one six and six different sides that could be rolled. As a percent, it would be 16.6 %. The probability of rolling an odd number on the second roll would be a 3/6 chance, which as a percent is 50 %. For the second question, both probabilities are 33 % because in both instances you are drawing three cards from nine total, so it would be 3/9. For the third question, the probability of drawing a blue marble is 3/5, because there are three blue marbles and five total marbles. As a percent, this is 60 %. Following this up with a green marble would be 2/4, because there are now 2 green marbles and four total marbles. One of the marbles was not replaced, so we have one less marble. 2/4 as a percent  is 50%.