Final answer:
The probability cannot be calculated exactly without knowing Andy Warhol's IQ, but it would be very low because he was a successful artist.
Step-by-step explanation:
To find the probability that an American has a lower IQ than Andy Warhol, we need to compare Andy Warhol's IQ to the IQ distribution of Americans. Unfortunately, the given information does not provide any specific data about Andy Warhol's IQ. Therefore, it is not possible to calculate the exact probability.
However, we can make an assumption based on the given information that the majority of people have an IQ score between 85 and 115. Since Andy Warhol was a successful artist, we can assume that his IQ would be above average. Therefore, the probability of an American having a lower IQ than Andy Warhol would be very low.