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A pair of dice are tossed twice. Find the probability that the first roll is a total of at least 7 and the second roll is a total of at least 10.

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Answer: 0.0972

Explanation:

To find the probability that the first roll is a total of at least 7 and the second roll is a total of at least 10, we need to find the probabilities of each event separately and then multiply them together.

First, let's find the probability of the first roll being a total of at least 7. There are a total of 36 possible outcomes when rolling a pair of dice (6 sides on each die, so 6 x 6 = 36). To get a total of at least 7, the following outcomes are possible:

7: (1, 6), (2, 5), (3, 4), (4, 3), (5, 2), (6, 1)

8: (2, 6), (3, 5), (4, 4), (5, 3), (6, 2)

9: (3, 6), (4, 5), (5, 4), (6, 3)

10: (4, 6), (5, 5), (6, 4)

11: (5, 6), (6, 5)

12: (6, 6)

There are 21 successful outcomes out of the total 36 possibilities. So, the probability of getting a total of at least 7 in the first roll is:

P(at least 7) = 21/36

Next, let's find the probability of the second roll being a total of at least 10. The following outcomes are possible:

10: (4, 6), (5, 5), (6, 4)

11: (5, 6), (6, 5)

12: (6, 6)

There are 6 successful outcomes out of the total 36 possibilities. So, the probability of getting a total of at least 10 in the second roll is:

P(at least 10) = 6/36

Now, to find the probability that both events happen, we multiply the probabilities of each event:

P(first roll at least 7 and second roll at least 10) = P(at least 7) * P(at least 10) = (21/36) * (6/36)

P(first roll at least 7 and second roll at least 10) = 126/1296

So, the probability that the first roll is a total of at least 7 and the second roll is a total of at least 10 is 126/1296, or approximately 0.0972 (rounded to four decimal places).

User Jody Klymak
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