Final answer:
The probability that Jan takes out a dime is 1, as there are only dimes in her pocket.
Step-by-step explanation:
The student question is about determining the probability of an event occurring which involves basic probability concepts. Since Jan has three dimes in her pocket and nothing else, when she takes out one coin, the probability that it is a dime is certain because dimes are the only kind of coin in her pocket. The probability is 1 (which is the same as 100%) because there is no chance of pulling out any other type of coin. This simple probability case highlights a situation where the event's probability reaches its maximum certainty, emphasizing the fundamental concept that when the outcome is inevitable, the probability equals 1 or 100%.