A town has two shopping malls. A survey conducted on the shopping preferences of the town's residents showed that 62% of the residents visit Comet Mall, 73% of the residents visit Star Mall, and 48% of the residents visit both malls.
Since 48% shop at both, 14% shop at Willow Creek only, and 25% shop at 2 Harbors only. So the probability of shopping at at least one is 48% + 14% + 25% = 87%, or 0.87 (A)