Algebra 2 probability

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5. A box contains 5 triangles, 6 circles, and 4 squares. If a figure is removed, replaced, and a second figure is picked, what is the probability that a triangle and then a circle will be picked?

6. A bag contains 5 red marbles and 4 white marbles. A marble is selected from the bag, then replaced, and a second selection is made. What is the probability of selecting 2 red marbles?

7. A die is rolled 3 times. Find the probability of each event.
a 1 or a 2 is rolled, then a 3, then a 5 or a 6

Rissy Roo -

5. A box contains 5 triangles, 6 circles, and 4 squares. If a figure is removed, replaced, and a second figure is picked, what is the probability that a triangle and then a circle will be picked?

P(a triangle and then a circle) = (5/15)(6/15) = 2/15


6. A bag contains 5 red marbles and 4 white marbles. A marble is selected from the bag, then replaced, and a second selection is made. What is the probability of selecting 2 red marbles?

P(selecting 2 red marbles) = (5/9)(5/9) = 25 / 81


7. A die is rolled 3 times. Find the probability of each event.
a 1 or a 2 is rolled, then a 3, then a 5 or a 6


P( 1 or a 2 is rolled, then a 3, then a 5 or a 6) = (2/6)(1/6)(2/6) = 1/54

Hope that helps