Conditional probablility P(A/B) = P(A and B) / P(B). Here, A is sum of two dice being greater than or equal to 9 and B is at least one of the dice showing 6. Number of ways two dice faces can sum up to 9 = (3, 6), (4, 5), (4, 6), (5, 4), (5, 5), (5, 6), (6, 3), (6, 4), (6, 5), (6, 6) = 10 ways. Number of ways that at least one of the dice must show 6 = (1, 6), (2, 6), (3, 6), (4, 6), (5, 6), (6, 6), (6, 5), (6, 4), (6, 3), (6, 2), (6, 1) = 11 ways. Number of ways of rolling a number greater than or equal to 9 and at least one of the dice showing 6 = (3, 6), (4, 6), (5, 6), (6, 3), (6, 4), (6, 5), (6, 6) = 7 ways. Probability of rolling a number greater than or equal to 9 given that at least one of the dice must show a 6 = 7 / 11
Answer:
I am only a 7th grader so I will probably get this incorrect but I think the correct answer is A.
Step-by-step explanation:
The best way to answer this item is to use the Substitution method. Substitute the value of y from the first equation to the y of the second equation such that the second equation becomes,
-4x + 3(x - 4) = -3
Simplifying the equation,
-x = 9
Dividing both sides by -1 gives an answer of,
<em>x = -9</em>
Then, substitute the value of x in the first equation.
y = -9 - 4
<em> y = -13</em>
The answer to this item is letter B.
Sorry i cant see the picture so well