Final answer:
The probability that a Target shopper will not be drinking Starbucks and not have kids with them is calculated using the principle of complementary probabilities, yielding an answer of 25%.
Step-by-step explanation:
To calculate the probability that a shopper at Target will not be drinking Starbucks and also not have kids with them, we can use the principle of complementary probabilities. The complementary probability of an event is 1 minus the probability of the event occurring.
Given:
- The probability that a shopper is drinking Starbucks (S) is 25%, or P(S) = 0.25.
- The probability that they have kids with them (K) is 65%, or P(K) = 0.65.
- The probability that they have both Starbucks and kids with them is 15%, or P(S ∩ K) = 0.15.
To find the probability of neither, we use:
P(neither) = 1 - P(S ∪ K)
But first, we need to find P(S ∪ K) by using the formula:
P(S ∪ K) = P(S) + P(K) - P(S ∩ K)
Plugging in the values we get:
P(S ∪ K) = 0.25 + 0.65 - 0.15 = 0.75
Now, we calculate the complementary probability:
P(neither) = 1 - P(S ∪ K) = 1 - 0.75 = 0.25 or 25%
Therefore, the correct answer is (C) 25%.