Answer:
the probability that a randomly selected item has neither D1 nor D2 is 87%.
Explanation:
Let's use the formula for the probability of the complement event to calculate the probability that a randomly selected item has neither D1 nor D2:
P(neither D1 nor D2) = 1 - P(D1 or D2)
We know that 5% have D1, 10% have D2, and 2% have both defects. The probability of an item having D1 or D2 (or both) is:
P(D1 or D2) = P(D1) + P(D2) - P(D1 and D2)
where P(D1 and D2) represents the probability that an item has both D1 and D2, which is 2% in this case.
Substituting the given values, we get:
P(D1 or D2) = 5% + 10% - 2% = 13%
So the probability of an item having neither D1 nor D2 is:
P(neither D1 nor D2) = 1 - P(D1 or D2) = 1 - 13% = 87%
Therefore, the probability that a randomly selected item has neither D1 nor D2 is 87%.