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The probability of the question being solved is the probability of at least one of them solving it. We can use the formula:
P(A ∪ B) = P(A) + P(B) - P(A ∩ B)
where P(A ∪ B) is the probability of the question being solved, P(A) is the probability of A solving it, P(B) is the probability of B solving it, and P(A ∩ B) is the probability of both A and B solving it.
Assuming A and B are independent, we have:
P(A ∩ B) = P(A) ×P(B) = (1/2) × (2/3) = 1/3
Now, we can plug in the values:
P(A ∪ B) = P(A) + P(B) - P(A ∩ B)
= (1/2) + (2/3) - (1/3)
= 1/2 + 1/3
= 5/6
So, the probability of the question being solved is 5/6.
To find the probability of the question being unsolved, we can use the complement rule:
P(unsolved) = 1 - P(solved)
We already found the probability of the question being solved:
P(solved) = 5/6
So, the probability of the question being unsolved is:
P(unsolved) = 1 - 5/6
= 1/6
Therefore, the probability of the question being unsolved is 1/6.
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