Final answer:
The question cannot be answered without additional information or a graph showing the rates at which Sam and Jane learn words over time.
Step-by-step explanation:
The information provided does not include the necessary data or graph to accurately determine when Sam and Jane will have learned an equal number of words. To answer this question, we would need the rates at which both individuals are learning words over time, or a graph that shows this relationship.
Without this information, we are unable to calculate the specific point in time at which they will have learned the same number of words.