Final answer:
Jim's sister is currently 2x - 2 years old; we derive this by knowing Jim will be x years old in two years and his sister will be twice his age at that time.
Step-by-step explanation:
The student's question revolves around determining the current age of Jim's sister. Since Jim will be x years old in two years, and his sister will be twice as old as he will be at that time, we can set up an equation to find her current age. If x is Jim's age in two years, his sister will be 2x years old at the same time.
However, we want to find her age now, not in two years. Since both Jim and his sister are getting older at the same rate, we need to subtract two years from his sister's future age to determine her current age. Therefore, Jim's sister's age right now is 2x - 2 years.